Porosity: Condition of having pores or open spaces. This often refers to bones, bone implants, or bone cements, but can refer to the porous state of any solid substance.Dental Casting Technique: The process of producing a form or impression made of metal or plaster using a mold.Corrosion Casting: A tissue preparation technique that involves the injecting of plastic (acrylates) into blood vessels or other hollow viscera and treating the tissue with a caustic substance. This results in a negative copy or a solid replica of the enclosed space of the tissue that is ready for viewing under a scanning electron microscope.Aluminum Compounds: Inorganic compounds that contain aluminum as an integral part of the molecule.Aluminum Hydroxide: A compound with many biomedical applications: as a gastric antacid, an antiperspirant, in dentifrices, as an emulsifier, as an adjuvant in bacterins and vaccines, in water purification, etc.Casts, Surgical: Dressings made of fiberglass, plastic, or bandage impregnated with plaster of paris used for immobilization of various parts of the body in cases of fractures, dislocations, and infected wounds. In comparison with plaster casts, casts made of fiberglass or plastic are lightweight, radiolucent, able to withstand moisture, and less rigid.Aluminum Oxide: An oxide of aluminum, occurring in nature as various minerals such as bauxite, corundum, etc. It is used as an adsorbent, desiccating agent, and catalyst, and in the manufacture of dental cements and refractories.Inlay Casting Wax: A mixture of several dental waxes, usually containing paraffin wax, ceresin, beeswax, resins, and other natural and synthetic waxes. It is used for making patterns to determine the shape of the metallic framework and other parts of removable partial dentures. (From Jablonski's Dictionary of Dentistry, 1992, p868)Materials Testing: The testing of materials and devices, especially those used for PROSTHESES AND IMPLANTS; SUTURES; TISSUE ADHESIVES; etc., for hardness, strength, durability, safety, efficacy, and biocompatibility.Titanium: A dark-gray, metallic element of widespread distribution but occurring in small amounts; atomic number, 22; atomic weight, 47.90; symbol, Ti; specific gravity, 4.5; used for fixation of fractures. (Dorland, 28th ed)Hardness: The mechanical property of material that determines its resistance to force. HARDNESS TESTS measure this property.Differential Thermal Analysis: Technique by which phase transitions of chemical reactions can be followed by observation of the heat absorbed or liberated.Microscopy, Electron, Scanning: Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY.Chromium Alloys: Specific alloys not less than 85% chromium and nickel or cobalt, with traces of either nickel or cobalt, molybdenum, and other substances. They are used in partial dentures, orthopedic implants, etc.Dental Alloys: A mixture of metallic elements or compounds with other metallic or metalloid elements in varying proportions for use in restorative or prosthetic dentistry.Compressive Strength: The maximum compression a material can withstand without failure. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed, p427)Haversian System: A circular structural unit of bone tissue. It consists of a central hole, the Haversian canal through which blood vessels run, surrounded by concentric rings, called lamellae.Surface Properties: Characteristics or attributes of the outer boundaries of objects, including molecules.Gold Alloys: Alloys that contain a high percentage of gold. They are used in restorative or prosthetic dentistry.Metallurgy: The science, art, or technology dealing with processes involved in the separation of metals from their ores, the technique of making or compounding the alloys, the techniques of working or heat-treating metals, and the mining of metals. It includes industrial metallurgy as well as metallurgical techniques employed in the preparation and working of metals used in dentistry, with special reference to orthodontic and prosthodontic appliances. (From Jablonski, Dictionary of Dentistry, 1992, p494)Crowns: A prosthetic restoration that reproduces the entire surface anatomy of the visible natural crown of a tooth. It may be partial (covering three or more surfaces of a tooth) or complete (covering all surfaces). It is made of gold or other metal, porcelain, or resin.Metal Ceramic Alloys: The fusion of ceramics (porcelain) to an alloy of two or more metals for use in restorative and prosthodontic dentistry. Examples of metal alloys employed include cobalt-chromium, gold-palladium, gold-platinum-palladium, and nickel-based alloys.Tissue Scaffolds: Cell growth support structures composed of BIOCOMPATIBLE MATERIALS. They are specially designed solid support matrices for cell attachment in TISSUE ENGINEERING and GUIDED TISSUE REGENERATION uses.Dental Marginal Adaptation: The degree of approximation or fit of filling material or dental prosthetic to the tooth surface. A close marginal adaptation and seal at the interface is important for successful dental restorations.Vacuum: A space in which the pressure is far below atmospheric pressure so that the remaining gases do not affect processes being carried on in the space.Polyesters: Polymers of organic acids and alcohols, with ester linkages--usually polyethylene terephthalate; can be cured into hard plastic, films or tapes, or fibers which can be woven into fabrics, meshes or velours.Biocompatible Materials: Synthetic or natural materials, other than DRUGS, that are used to replace or repair any body TISSUES or bodily function.Silicon Dioxide: Transparent, tasteless crystals found in nature as agate, amethyst, chalcedony, cristobalite, flint, sand, QUARTZ, and tridymite. The compound is insoluble in water or acids except hydrofluoric acid.Dental Casting Investment: Material from which the casting mold is made in the fabrication of gold or cobalt-chromium castings. (Boucher's Clinical Dental Terminology, 4th ed, p168)Tissue Engineering: Generating tissue in vitro for clinical applications, such as replacing wounded tissues or impaired organs. The use of TISSUE SCAFFOLDING enables the generation of complex multi-layered tissues and tissue structures.Corrosion: The gradual destruction of a metal or alloy due to oxidation or action of a chemical agent. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Electron Probe Microanalysis: Identification and measurement of ELEMENTS and their location based on the fact that X-RAYS emitted by an element excited by an electron beam have a wavelength characteristic of that element and an intensity related to its concentration. It is performed with an electron microscope fitted with an x-ray spectrometer, in scanning or transmission mode.Tenotomy: Surgical division of a tendon for relief of a deformity that is caused by congenital or acquired shortening of a muscle (Stedman, 27th ed). Tenotomy is performed in order to lengthen a muscle that has developed improperly, or become shortened and is resistant to stretching.Tooth Preparation, Prosthodontic: The selected form given to a natural tooth when it is reduced by instrumentation to receive a prosthesis (e.g., artificial crown or a retainer for a fixed or removable prosthesis). The selection of the form is guided by clinical circumstances and physical properties of the materials that make up the prosthesis. (Boucher's Clinical Dental Terminology, 4th ed, p239)Tensile Strength: The maximum stress a material subjected to a stretching load can withstand without tearing. (McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed, p2001)Alum Compounds: Aluminum metal sulfate compounds used medically as astringents and for many industrial purposes. They are used in veterinary medicine for the treatment of ulcerative stomatitis, leukorrhea, conjunctivitis, pharyngitis, metritis, and minor wounds.Quartz: Quartz (SiO2). A glassy or crystalline form of silicon dioxide. Many colored varieties are semiprecious stones. (From Grant & Hackh's Chemical Dictionary, 5th ed)Bone Substitutes: Synthetic or natural materials for the replacement of bones or bone tissue. They include hard tissue replacement polymers, natural coral, hydroxyapatite, beta-tricalcium phosphate, and various other biomaterials. The bone substitutes as inert materials can be incorporated into surrounding tissue or gradually replaced by original tissue.Ceramics: Products made by baking or firing nonmetallic minerals (clay and similar materials). In making dental restorations or parts of restorations the material is fused porcelain. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed & Boucher's Clinical Dental Terminology, 4th ed)Bone and Bones: A specialized CONNECTIVE TISSUE that is the main constituent of the SKELETON. The principle cellular component of bone is comprised of OSTEOBLASTS; OSTEOCYTES; and OSTEOCLASTS, while FIBRILLAR COLLAGENS and hydroxyapatite crystals form the BONE MATRIX.Clubfoot: A deformed foot in which the foot is plantarflexed, inverted and adducted.Silicon: A trace element that constitutes about 27.6% of the earth's crust in the form of SILICON DIOXIDE. It does not occur free in nature. Silicon has the atomic symbol Si, atomic number 14, and atomic weight [28.084; 28.086].Zirconium: Zirconium. A rather rare metallic element, atomic number 40, atomic weight 91.22, symbol Zr. (From Dorland, 28th ed)Dental Clasps: Metal devices for fastening together two or more parts of dental prostheses for stabilizing or retaining them by attachment to abutment teeth. For a precision attachment for a partial denture DENTURE PRECISION ATTACHMENT is available.Fluorides: Inorganic salts of hydrofluoric acid, HF, in which the fluorine atom is in the -1 oxidation state. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed) Sodium and stannous salts are commonly used in dentifrices.Microradiography: Production of a radiographic image of a small or very thin object on fine-grained photographic film under conditions which permit subsequent microscopic examination or enlargement of the radiograph at linear magnifications of up to several hundred and with a resolution approaching the resolving power of the photographic emulsion (about 1000 lines per millimeter).Contracture: Prolonged shortening of the muscle or other soft tissue around a joint, preventing movement of the joint.Polymers: Compounds formed by the joining of smaller, usually repeating, units linked by covalent bonds. These compounds often form large macromolecules (e.g., BIOPOLYMERS; PLASTICS).Hardness Tests: A test to determine the relative hardness of a metal, mineral, or other material according to one of several scales, such as Brinell, Mohs, Rockwell, Vickers, or Shore. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Stress, Mechanical: A purely physical condition which exists within any material because of strain or deformation by external forces or by non-uniform thermal expansion; expressed quantitatively in units of force per unit area.Diaphyses: The shaft of long bones.Astringents: Agents, usually topical, that cause the contraction of tissues for the control of bleeding or secretions.Powders: Substances made up of an aggregation of small particles, as that obtained by grinding or trituration of a solid drug. In pharmacy it is a form in which substances are administered. (From Dorland, 28th ed)Dental Stress Analysis: The description and measurement of the various factors that produce physical stress upon dental restorations, prostheses, or appliances, materials associated with them, or the natural oral structures.Immobilization: The restriction of the MOVEMENT of whole or part of the body by physical means (RESTRAINT, PHYSICAL) or chemically by ANALGESIA, or the use of TRANQUILIZING AGENTS or NEUROMUSCULAR NONDEPOLARIZING AGENTS. It includes experimental protocols used to evaluate the physiologic effects of immobility.Argon: Argon. A noble gas with the atomic symbol Ar, atomic number 18, and atomic weight 39.948. It is used in fluorescent tubes and wherever an inert atmosphere is desired and nitrogen cannot be used.Phosphines: Inorganic or organic compounds derived from phosphine (PH3) by the replacement of H atoms. (From Grant & Hackh's Chemical Dictionary, 5th ed)Spectrophotometry, Atomic: Spectrophotometric techniques by which the absorption or emmision spectra of radiation from atoms are produced and analyzed.Osteomalacia: Disorder caused by an interruption of the mineralization of organic bone matrix leading to bone softening, bone pain, and weakness. It is the adult form of rickets resulting from disruption of VITAMIN D; PHOSPHORUS; or CALCIUM homeostasis.X-Ray Microtomography: X-RAY COMPUTERIZED TOMOGRAPHY with resolution in the micrometer range.Femur: The longest and largest bone of the skeleton, it is situated between the hip and the knee.Dental Materials: Materials used in the production of dental bases, restorations, impressions, prostheses, etc.Citric Acid: A key intermediate in metabolism. It is an acid compound found in citrus fruits. The salts of citric acid (citrates) can be used as anticoagulants due to their calcium chelating ability.HornsFracture Fixation: The use of metallic devices inserted into or through bone to hold a fracture in a set position and alignment while it heals.Splints: Rigid or flexible appliances used to maintain in position a displaced or movable part or to keep in place and protect an injured part. (Dorland, 28th ed)WeldingSilver: Silver. An element with the atomic symbol Ag, atomic number 47, and atomic weight 107.87. It is a soft metal that is used medically in surgical instruments, dental prostheses, and alloys. Long-continued use of silver salts can lead to a form of poisoning known as ARGYRIA.Durapatite: The mineral component of bones and teeth; it has been used therapeutically as a prosthetic aid and in the prevention and treatment of osteoporosis.Silicates: The generic term for salts derived from silica or the silicic acids. They contain silicon, oxygen, and one or more metals, and may contain hydrogen. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th Ed)Denture Design: The plan, delineation, and location of actual structural elements of dentures. The design can relate to retainers, stress-breakers, occlusal rests, flanges, framework, lingual or palatal bars, reciprocal arms, etc.Muscle Hypertonia: Abnormal increase in skeletal or smooth muscle tone. Skeletal muscle hypertonicity may be associated with PYRAMIDAL TRACT lesions or BASAL GANGLIA DISEASES.Polyvinyl Alcohol: A polymer prepared from polyvinyl acetates by replacement of the acetate groups with hydroxyl groups. It is used as a pharmaceutic aid and ophthalmic lubricant as well as in the manufacture of surface coatings artificial sponges, cosmetics, and other products.Administration, Buccal: Administration of a soluble dosage form between the cheek and gingiva. It may involve direct application of a drug onto the buccal mucosa, as by painting or spraying.Heart Septal Defects, Ventricular: Developmental abnormalities in any portion of the VENTRICULAR SEPTUM resulting in abnormal communications between the two lower chambers of the heart. Classification of ventricular septal defects is based on location of the communication, such as perimembranous, inlet, outlet (infundibular), central muscular, marginal muscular, or apical muscular defect.Dental Impression Materials: Substances used to create an impression, or negative reproduction, of the teeth and dental arches. These materials include dental plasters and cements, metallic oxide pastes, silicone base materials, or elastomeric materials.Implants, Experimental: Artificial substitutes for body parts and materials inserted into organisms during experimental studies.Calcium Phosphates: Calcium salts of phosphoric acid. These compounds are frequently used as calcium supplements.Methylmethacrylates: The methyl esters of methacrylic acid that polymerize easily and are used as tissue cements, dental materials, and absorbent for biological substances.Dental Polishing: Creation of a smooth and glossy surface finish on a denture or amalgam.Polyglycolic Acid: A biocompatible polymer used as a surgical suture material.Ulna Fractures: Fractures of the larger bone of the forearm.Bone Regeneration: Renewal or repair of lost bone tissue. It excludes BONY CALLUS formed after BONE FRACTURES but not yet replaced by hard bone.Heart Defects, Congenital: Developmental abnormalities involving structures of the heart. These defects are present at birth but may be discovered later in life.Water: A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Particle Size: Relating to the size of solids.Denture, Partial, Removable: A partial denture designed and constructed to be removed readily from the mouth.Bowhead Whale: The species Balaena mysticetus, in the family Balaenidae, found in the colder waters of the Northern Hemisphere. The common name is derived from the extreme arching of the lower jaw.Hot Temperature: Presence of warmth or heat or a temperature notably higher than an accustomed norm.Elastic Modulus: Numerical expression indicating the measure of stiffness in a material. It is defined by the ratio of stress in a unit area of substance to the resulting deformation (strain). This allows the behavior of a material under load (such as bone) to be calculated.Shear Strength: The internal resistance of a material to moving some parts of it parallel to a fixed plane, in contrast to stretching (TENSILE STRENGTH) or compression (COMPRESSIVE STRENGTH). Ionic crystals are brittle because, when subjected to shear, ions of the same charge are brought next to each other, which causes repulsion.Heart Septal Defects, Atrial: Developmental abnormalities in any portion of the ATRIAL SEPTUM resulting in abnormal communications between the two upper chambers of the heart. Classification of atrial septal defects is based on location of the communication and types of incomplete fusion of atrial septa with the ENDOCARDIAL CUSHIONS in the fetal heart. They include ostium primum, ostium secundum, sinus venosus, and coronary sinus defects.Wettability: The quality or state of being wettable or the degree to which something can be wet. This is also the ability of any solid surface to be wetted when in contact with a liquid whose surface tension is reduced so that the liquid spreads over the surface of the solid.Denture, Partial: A denture replacing one or more (but not all) natural teeth. It is supported and retained by underlying tissue and some or all of the remaining teeth.X-Ray Diffraction: The scattering of x-rays by matter, especially crystals, with accompanying variation in intensity due to interference effects. Analysis of the crystal structure of materials is performed by passing x-rays through them and registering the diffraction image of the rays (CRYSTALLOGRAPHY, X-RAY). (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Time Factors: Elements of limited time intervals, contributing to particular results or situations.Ilium: The largest of three bones that make up each half of the pelvic girdle.Plant Roots: The usually underground portions of a plant that serve as support, store food, and through which water and mineral nutrients enter the plant. (From American Heritage Dictionary, 1982; Concise Dictionary of Biology, 1990)Biomechanical Phenomena: The properties, processes, and behavior of biological systems under the action of mechanical forces.Alloys: A mixture of metallic elements or compounds with other metallic or metalloid elements in varying proportions.Chemistry, Pharmaceutical: Chemistry dealing with the composition and preparation of agents having PHARMACOLOGIC ACTIONS or diagnostic use.Palladium: A chemical element having an atomic weight of 106.4, atomic number of 46, and the symbol Pd. It is a white, ductile metal resembling platinum, and following it in abundance and importance of applications. It is used in dentistry in the form of gold, silver, and copper alloys.Denture, Partial, Fixed: A partial denture attached to prepared natural teeth, roots, or implants by cementation.Tablets: Solid dosage forms, of varying weight, size, and shape, which may be molded or compressed, and which contain a medicinal substance in pure or diluted form. (Dorland, 28th ed)Dental Soldering: The joining of pieces of metal through the use of an alloy which has a lower melting point, usually at least 100 degrees Celsius below the fusion temperature of the parts being soldered. In dentistry, soldering is used for joining components of a dental appliance, as in assembling a bridge, joining metals to orthodontic bands, or adding to the bulk of certain structures, such as the establishment of proper contact areas on inlays and crowns with adjacent teeth. (Illustrated Dictionary of Dentistry, 1982)Radius FracturesInlays: Restorations of metal, porcelain, or plastic made to fit a cavity preparation, then cemented into the tooth. Onlays are restorations which fit into cavity preparations and overlay the occlusal surface of a tooth or teeth. Onlays are retained by frictional or mechanical factors.Bone Cements: Adhesives used to fix prosthetic devices to bones and to cement bone to bone in difficult fractures. Synthetic resins are commonly used as cements. A mixture of monocalcium phosphate, monohydrate, alpha-tricalcium phosphate, and calcium carbonate with a sodium phosphate solution is also a useful bone paste.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Equipment Failure Analysis: The evaluation of incidents involving the loss of function of a device. These evaluations are used for a variety of purposes such as to determine the failure rates, the causes of failures, costs of failures, and the reliability and maintainability of devices.Nanostructures: Materials which have structured components with at least one dimension in the range of 1 to 100 nanometers. These include NANOCOMPOSITES; NANOPARTICLES; NANOTUBES; and NANOWIRES.Dental Prosthesis Retention: Holding a DENTAL PROSTHESIS in place by its design, or by the use of additional devices or adhesives.Calcium Compounds: Inorganic compounds that contain calcium as an integral part of the molecule.Polyurethanes: A group of thermoplastic or thermosetting polymers containing polyisocyanate. They are used as ELASTOMERS, as coatings, as fibers and as foams.Aluminum: A metallic element that has the atomic number 13, atomic symbol Al, and atomic weight 26.98.Bone Remodeling: The continuous turnover of BONE MATRIX and mineral that involves first an increase in BONE RESORPTION (osteoclastic activity) and later, reactive BONE FORMATION (osteoblastic activity). The process of bone remodeling takes place in the adult skeleton at discrete foci. The process ensures the mechanical integrity of the skeleton throughout life and plays an important role in calcium HOMEOSTASIS. An imbalance in the regulation of bone remodeling's two contrasting events, bone resorption and bone formation, results in many of the metabolic bone diseases, such as OSTEOPOROSIS.Beryllium: Beryllium. An element with the atomic symbol Be, atomic number 4, and atomic weight 9.01218. Short exposure to this element can lead to a type of poisoning known as BERYLLIOSIS.Antacids: Substances that counteract or neutralize acidity of the GASTROINTESTINAL TRACT.Analysis of Variance: A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable.Nanocomposites: Nanometer-scale composite structures composed of organic molecules intimately incorporated with inorganic molecules. (Glossary of Biotechnology and Nanobiotechology Terms, 4th ed)Air Abrasion, Dental: A technique using a pneumatic, high-pressure stream of aluminum oxide to remove DENTAL ENAMEL; DENTIN; and restorative materials from teeth. In contrast to using DENTAL HIGH-SPEED EQUIPMENT, this method usually requires no dental anesthesia (ANESTHESIA, DENTAL) and reduces risks of tooth chipping and microfracturing. It is used primarily for routine DENTAL CAVITY PREPARATION.Permeability: Property of membranes and other structures to permit passage of light, heat, gases, liquids, metabolites, and mineral ions.Denture Retention: The retention of a denture in place by design, device, or adhesion.Apatites: A group of phosphate minerals that includes ten mineral species and has the general formula X5(YO4)3Z, where X is usually calcium or lead, Y is phosphorus or arsenic, and Z is chlorine, fluorine, or OH-. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Nanofibers: Submicron-sized fibers with diameters typically between 50 and 500 nanometers. The very small dimension of these fibers can generate a high surface area to volume ratio, which makes them potential candidates for various biomedical and other applications.Fraxinus: A plant genus of the family OLEACEAE. Members contain secoiridoid glucosides.Elasticity: Resistance and recovery from distortion of shape.Dental Prosthesis, Implant-Supported: A prosthesis that gains its support, stability, and retention from a substructure that is implanted under the soft tissues of the basal seat of the device and is in contact with bone. (From Boucher's Clinical Dental Terminology, 4th ed)Osteogenesis: The process of bone formation. Histogenesis of bone including ossification.Aluminum Silicates: Any of the numerous types of clay which contain varying proportions of Al2O3 and SiO2. They are made synthetically by heating aluminum fluoride at 1000-2000 degrees C with silica and water vapor. (From Hawley's Condensed Chemical Dictionary, 11th ed)Boron: A trace element with the atomic symbol B, atomic number 5, and atomic weight [10.806; 10.821]. Boron-10, an isotope of boron, is used as a neutron absorber in BORON NEUTRON CAPTURE THERAPY.Manipulation, Orthopedic: The planned and carefully managed manual movement of the musculoskeletal system, extremities, and spine to produce increased motion. The term is sometimes used to denote a precise sequence of movements of a joint to determine the presence of disease or to reduce a dislocation. In the case of fractures, orthopedic manipulation can produce better position and alignment of the fracture. (From Blauvelt & Nelson, A Manual of Orthopaedic Terminology, 5th ed, p264)Dental Bonding: An adhesion procedure for orthodontic attachments, such as plastic DENTAL CROWNS. This process usually includes the application of an adhesive material (DENTAL CEMENTS) and letting it harden in-place by light or chemical curing.Adsorption: The adhesion of gases, liquids, or dissolved solids onto a surface. It includes adsorptive phenomena of bacteria and viruses onto surfaces as well. ABSORPTION into the substance may follow but not necessarily.Filtration: A process of separating particulate matter from a fluid, such as air or a liquid, by passing the fluid carrier through a medium that will not pass the particulates. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Fracture Healing: The physiological restoration of bone tissue and function after a fracture. It includes BONY CALLUS formation and normal replacement of bone tissue.Magnesium Oxide: Magnesium oxide (MgO). An inorganic compound that occurs in nature as the mineral periclase. In aqueous media combines quickly with water to form magnesium hydroxide. It is used as an antacid and mild laxative and has many nonmedicinal uses.Physicochemical Phenomena: The physical phenomena describing the structure and properties of atoms and molecules, and their reaction and interaction processes.Tibia: The second longest bone of the skeleton. It is located on the medial side of the lower leg, articulating with the FIBULA laterally, the TALUS distally, and the FEMUR proximally.Braces: Orthopedic appliances used to support, align, or hold parts of the body in correct position. (Dorland, 28th ed)Reducing Agents: Materials that add an electron to an element or compound, that is, decrease the positiveness of its valence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)Acrylic ResinsNiobium: Niobium. A metal element atomic number 41, atomic weight 92.906, symbol Nb. (From Dorland, 28th ed)Physicochemical Processes: Physical reactions involved in the formation of or changes in the structure of atoms and molecules and their interactions.Soil: The unconsolidated mineral or organic matter on the surface of the earth that serves as a natural medium for the growth of land plants.Radius: The outer shorter of the two bones of the FOREARM, lying parallel to the ULNA and partially revolving around it.Chitosan: Deacetylated CHITIN, a linear polysaccharide of deacetylated beta-1,4-D-glucosamine. It is used in HYDROGEL and to treat WOUNDS.De Quervain Disease: Stenosing tenosynovitis of the abductor pollicis longus and extensor pollicis brevis tendons in the first dorsal wrist compartment. The presenting symptoms are usually pain and tenderness at the radial styloid. The cause is almost always related to OVERUSE INJURY or is associated with RHEUMATOID ARTHRITIS.Temperature: The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.Ursidae: The family of carnivorous or omnivorous bears, having massive bodies, coarse heavy fur, relatively short limbs, and almost rudimentary tails.Antiperspirants: Agents that are put on the SKIN to reduce SWEATING or prevent excess sweating (HYPERHIDROSIS).Adjuvants, Immunologic: Substances that augment, stimulate, activate, potentiate, or modulate the immune response at either the cellular or humoral level. The classical agents (Freund's adjuvant, BCG, Corynebacterium parvum, et al.) contain bacterial antigens. Some are endogenous (e.g., histamine, interferon, transfer factor, tuftsin, interleukin-1). Their mode of action is either non-specific, resulting in increased immune responsiveness to a wide variety of antigens, or antigen-specific, i.e., affecting a restricted type of immune response to a narrow group of antigens. The therapeutic efficacy of many biological response modifiers is related to their antigen-specific immunoadjuvanticity.Lactic Acid: A normal intermediate in the fermentation (oxidation, metabolism) of sugar. The concentrated form is used internally to prevent gastrointestinal fermentation. (From Stedman, 26th ed)Equinus Deformity: Plantar declination of the foot.Osseointegration: The growth action of bone tissue as it assimilates surgically implanted devices or prostheses to be used as either replacement parts (e.g., hip) or as anchors (e.g., endosseous dental implants).Solubility: The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Bone Density: The amount of mineral per square centimeter of BONE. This is the definition used in clinical practice. Actual bone density would be expressed in grams per milliliter. It is most frequently measured by X-RAY ABSORPTIOMETRY or TOMOGRAPHY, X RAY COMPUTED. Bone density is an important predictor for OSTEOPOROSIS.Drug Compounding: The preparation, mixing, and assembling of a drug. (From Remington, The Science and Practice of Pharmacy, 19th ed, p1814)Heart Septal Defects: Abnormalities in any part of the HEART SEPTUM resulting in abnormal communication between the left and the right chambers of the heart. The abnormal blood flow inside the heart may be caused by defects in the ATRIAL SEPTUM, the VENTRICULAR SEPTUM, or both.CitratesHydrogels: Water swollen, rigid, 3-dimensional network of cross-linked, hydrophilic macromolecules, 20-95% water. They are used in paints, printing inks, foodstuffs, pharmaceuticals, and cosmetics. (Grant & Hackh's Chemical Dictionary, 5th ed)Biofouling: Process by which unwanted microbial, plant or animal materials or organisms accumulate on man-made surfaces.Glass: Hard, amorphous, brittle, inorganic, usually transparent, polymerous silicate of basic oxides, usually potassium or sodium. It is used in the form of hard sheets, vessels, tubing, fibers, ceramics, beads, etc.Dental Prosthesis Design: The plan and delineation of dental prostheses in general or a specific dental prosthesis. It does not include DENTURE DESIGN. The framework usually consists of metal.Fractures, Closed: Fractures in which the break in bone is not accompanied by an external wound.Dental Cements: Substances used to bond COMPOSITE RESINS to DENTAL ENAMEL and DENTIN. These bonding or luting agents are used in restorative dentistry, ROOT CANAL THERAPY; PROSTHODONTICS; and ORTHODONTICS.Sophora: A plant genus of the family FABACEAE.Polycarboxylate Cement: Water-soluble low-molecular-weight polymers of acrylic or methacrylic acid that form solid, insoluble products when mixed with specially prepared ZnO powder. The resulting cement adheres to dental enamel and is also used as a luting agent.Statistics, Nonparametric: A class of statistical methods applicable to a large set of probability distributions used to test for correlation, location, independence, etc. In most nonparametric statistical tests, the original scores or observations are replaced by another variable containing less information. An important class of nonparametric tests employs the ordinal properties of the data. Another class of tests uses information about whether an observation is above or below some fixed value such as the median, and a third class is based on the frequency of the occurrence of runs in the data. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1284; Corsini, Concise Encyclopedia of Psychology, 1987, p764-5)Occlusal Adjustment: Selective grinding of occlusal surfaces of the teeth in an effort to eliminate premature contacts and occlusal interferences; to establish optimal masticatory effectiveness, stable occlusal relationships, direction of main occlusal forces, and efficient multidirectional patterns, to improve functional relations and to induce physiologic stimulation of the masticatory system; to eliminate occlusal trauma; to eliminate abnormal muscle tension; to aid in the stabilization of orthodontic results; to treat periodontal and temporomandibular joint problems; and in restorative procedures. (From Jablonski, Dictionary of Dentistry, 1992)Heating: The application of heat to raise the temperature of the environment, ambient or local, or the systems for accomplishing this effect. It is distinguished from HEAT, the physical property and principle of physics.Computer-Aided Design: The use of computers for designing and/or manufacturing of anything, including drugs, surgical procedures, orthotics, and prosthetics.Cementation: The joining of objects by means of a cement (e.g., in fracture fixation, such as in hip arthroplasty for joining of the acetabular component to the femoral component). In dentistry, it is used for the process of attaching parts of a tooth or restorative material to a natural tooth or for the attaching of orthodontic bands to teeth by means of an adhesive.Organometallic Compounds: A class of compounds of the type R-M, where a C atom is joined directly to any other element except H, C, N, O, F, Cl, Br, I, or At. (Grant & Hackh's Chemical Dictionary, 5th ed)Osteocytes: Mature osteoblasts that have become embedded in the BONE MATRIX. They occupy a small cavity, called lacuna, in the matrix and are connected to adjacent osteocytes via protoplasmic projections called canaliculi.Zinc Phosphate Cement: A material used for cementation of inlays, crowns, bridges, and orthodontic appliances and occasionally as a temporary restoration. It is prepared by mixing zinc oxide and magnesium oxide powders with a liquid consisting principally of phosphoric acid, water, and buffers. (From Bouchers' Clinical Dental Terminology, 3d ed)Prosthesis Fitting: The fitting and adjusting of artificial parts of the body. (From Stedman's, 26th ed)Carboxymethylcellulose Sodium: A cellulose derivative which is a beta-(1,4)-D-glucopyranose polymer. It is used as a bulk laxative and as an emulsifier and thickener in cosmetics and pharmaceuticals and as a stabilizer for reagents.Decanoates: Salts and esters of the 10-carbon monocarboxylic acid-decanoic acid.Polymethyl Methacrylate: Polymerized methyl methacrylate monomers which are used as sheets, moulding, extrusion powders, surface coating resins, emulsion polymers, fibers, inks, and films (From International Labor Organization, 1983). This material is also used in tooth implants, bone cements, and hard corneal contact lenses.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Equipment Design: Methods of creating machines and devices.Phosphates: Inorganic salts of phosphoric acid.Glycols: A generic grouping for dihydric alcohols with the hydroxy groups (-OH) located on different carbon atoms. They are viscous liquids with high boiling points for their molecular weights.Traction: The pull on a limb or a part thereof. Skin traction (indirect traction) is applied by using a bandage to pull on the skin and fascia where light traction is required. Skeletal traction (direct traction), however, uses pins or wires inserted through bone and is attached to weights, pulleys, and ropes. (From Blauvelt & Nelson, A Manual of Orthopaedic Terminology, 5th ed)Deer: The family Cervidae of 17 genera and 45 species occurring nearly throughout North America, South America, and Eurasia, on most associated continental islands, and in northern Africa. Wild populations of deer have been established through introduction by people in Cuba, New Guinea, Australia, New Zealand, and other places where the family does not naturally occur. They are slim, long-legged and best characterized by the presence of antlers. Their habitat is forests, swamps, brush country, deserts, and arctic tundra. They are usually good swimmers; some migrate seasonally. (Walker's Mammals of the World, 5th ed, p1362)Absorbable Implants: Implants constructed of materials designed to be absorbed by the body without producing an immune response. They are usually composed of plastics and are frequently used in orthopedics and orthodontics.Platinum: Platinum. A heavy, soft, whitish metal, resembling tin, atomic number 78, atomic weight 195.09, symbol Pt. (From Dorland, 28th ed) It is used in manufacturing equipment for laboratory and industrial use. It occurs as a black powder (platinum black) and as a spongy substance (spongy platinum) and may have been known in Pliny's time as "alutiae".Microspheres: Small uniformly-sized spherical particles, of micrometer dimensions, frequently labeled with radioisotopes or various reagents acting as tags or markers.Rabbits: The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.Oxides: Binary compounds of oxygen containing the anion O(2-). The anion combines with metals to form alkaline oxides and non-metals to form acidic oxides.Renal Osteodystrophy: Decalcification of bone or abnormal bone development due to chronic KIDNEY DISEASES, in which 1,25-DIHYDROXYVITAMIN D3 synthesis by the kidneys is impaired, leading to reduced negative feedback on PARATHYROID HORMONE. The resulting SECONDARY HYPERPARATHYROIDISM eventually leads to bone disorders.Freeze Drying: Method of tissue preparation in which the tissue specimen is frozen and then dehydrated at low temperature in a high vacuum. This method is also used for dehydrating pharmaceutical and food products.Phenotype: The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.Imaging, Three-Dimensional: The process of generating three-dimensional images by electronic, photographic, or other methods. For example, three-dimensional images can be generated by assembling multiple tomographic images with the aid of a computer, while photographic 3-D images (HOLOGRAPHY) can be made by exposing film to the interference pattern created when two laser light sources shine on an object.Achilles Tendon: A fibrous cord that connects the muscles in the back of the calf to the HEEL BONE.Guided Tissue Regeneration: Procedures for enhancing and directing tissue repair and renewal processes, such as BONE REGENERATION; NERVE REGENERATION; etc. They involve surgically implanting growth conducive tracks or conduits (TISSUE SCAFFOLDING) at the damaged site to stimulate and control the location of cell repopulation. The tracks or conduits are made from synthetic and/or natural materials and may include support cells and induction factors for CELL GROWTH PROCESSES; or CELL MIGRATION.Magnesium Compounds: Inorganic compounds that contain magnesium as an integral part of the molecule.Polyethylene Terephthalates: Polyester polymers formed from terephthalic acid or its esters and ethylene glycol. They can be formed into tapes, films or pulled into fibers that are pressed into meshes or woven into fabrics.Hydrogel: A network of cross-linked hydrophilic macromolecules used in biomedical applications.Absorption: The physical or physiological processes by which substances, tissue, cells, etc. take up or take in other substances or energy.
Hydrogen picked up during melting and casting segregates at internal voids and discontinuities and produces these defects ... in ingots and castings) produces hydrogen gas porosity. By far, the most damaging effect of hydrogen in structural materials is ... This effect is seen in high strength structural steels, titanium alloys and aluminium alloys. Embrittlement of materials when ... Hydrogen may be picked up by metals during melting, casting, shaping and fabrication. They are also exposed to hydrogen during ...
Hydrogen gas porosity Inclusions in aluminium alloys Non-metallic inclusions for inclusions in steel Porosity sealing Rao 1999 ... Closed shrinkage defects, also known as shrinkage porosity, are defects that form within the casting. Isolated pools of liquid ... A casting defect is an undesired irregularity in a metal casting process. Some defects can be tolerated while others can be ... The following defects can occur in sand castings. Most of these also occur in other casting processes. Shrinkage defects can ...
The main types are: gas porosity, shrinkage defects, mold material defects, pouring metal defects, and metallurgical defects. ... The process is easily automated and more precise than sand casting. Common metals that are cast include cast iron, aluminium, ... Full-mold casting is an evaporative-pattern casting process which is a combination of sand casting and lost-foam casting. It ... The two main processes are lost-foam casting and full-mold casting. Lost-foam casting is a type of evaporative-pattern casting ...
... is an aluminium casting defect under the form of a porosity or void in an aluminium casting caused by a ... Hydrogen causes porosity in aluminum products leading to many casting defects, reduced mechanical properties like fatigue and ... Because the solubility of hydrogen in solid aluminium is much smaller than in liquid aluminium, when the aluminium freezes, the ... Aluminum smelters and aluminum foundries want to produce high quality aluminum and shape castings with minimum porosity. This ...
Previous information apply only for ingot casting which is now mostly obsolete with continuous casting and strip-casting ... Aluminium reacts with the dissolved gas to form aluminium oxide. The aluminum oxide precipitates provide the additional benefit ... but the carbon monoxide leaves blowhole type porosity distributed throughout the ingot. The porosity eliminates the pipe found ... The main disadvantage killed steels is that it suffers from deep pipe shrinkage defects. To minimize the amount of metal that ...
The main types are: gas porosity, shrinkage defects, mold material defects, pouring metal defects, and metallurgical defects. ... The process is easily automated and more precise than sand casting. Common metals that are cast include cast iron, aluminium, ... Defects[edit]. Main article: Casting defects. There are a number of problems that can be encountered during the casting process ... Sand casting[edit]. Main article: Sand casting. Sand casting is one of the most popular and simplest types of casting, and has ...
Refining is done to remove deleterious gases and elements from the molten metal to avoid casting defects. Material is added ... The most common metals processed are aluminium and cast iron. However, other metals, such as bronze, brass, steel, magnesium, ... In cases where porosity still remains present after the degassing process, porosity sealing can be accomplished through a ... size of the casting, and complexity of the casting. These mold processes include: Sand casting - Green or resin bonded sand ...
The alloys of aluminium, titanium and magnesium are valued for their high strength-to-weight ratios; magnesium can also provide ... Of all the metallic alloys in use today, the alloys of iron (steel, stainless steel, cast iron, tool steel, alloy steel) make ... The movement or displacement of such mobile defects is thermally activated, and thus limited by the rate of atomic diffusion. ... changes in the microstructure like grain growth and localized densification due to the elimination of intergranular porosity. ...
Manufacturing defects found in cast wheels include cavities or porosity and a different metallurgical microstructure, entailing ... After 1960's magnesium wheels were gradually replaced by aluminium alloy wheels on the mass market, but not from the ... And although cast wheels are more affordable than forged wheels, cast wheels are designed to be heavier than forged wheels for ... The original cast magnesium wheels were made beginning in the 1930s and their production continues today. Some of the biggest ...
... is used with almost any castable metal. However, aluminium alloys, copper alloys, and steel are the most ... uses gas pressure and a vacuum to improve the quality of the casting and minimize porosity. Typically VPC machines consist of ... a lot of labor is needed and occasional minute defects. However, the cost is still less than producing the same part by ... Lost-foam casting is a modern form of investment casting that eliminates certain steps in the process. Investment casting ...
Ceramic forming techniques include throwing, slipcasting, tape casting, freeze-casting, injection moulding, dry pressing, ... This step needs careful control, as rapid heating causes cracks and surface defects. The dried part is smaller than the green ... The Bayer process is still used to purify alumina for the ceramic and aluminium industries. Brothers Pierre and Jacques Curie ... Because there is usually no pressing and sintering, glass-ceramics do not contain the volume fraction of porosity typically ...
Other possible defects are gas porosity, shrinkage porosity, hot tears, and flow marks. Flow marks are marks left on the ... ferrous die casting is also possible.[6] Specific die casting alloys include: zinc aluminium; aluminium to, e.g. The Aluminum ... See also: Casting defect. After the shakeout of the casting it is inspected for defects. The most common defects are misruns ... When no porosity is allowed in a cast part then the pore-free casting process is used. It is identical to the standard process ...
... s are used for both cast and forged components, with the aluminium-containing alloys usually used for casting ... The oxide forms blackened areas called burns on the surface of the casting, and the liberated hydrogen may cause porosity. ... Soldering of magnesium alloys is feasible only for plugging surface defects in parts. The solders are even more corrosive than ... Sand, permanent mold and die casting methods are used, but plaster-of-Paris casting has not yet been perfected. Sand casting in ...
... aluminium-titanium, aluminium-neodymium and aluminium-silver sputter targets; aluminium-silicon alloys for cylinder liners; and ... As sprayed the billet porosity is typically 1-2% with a region of higher porosity in the splat-quenched region adjacent to the ... Spray forming, also known as spray casting, spray deposition and in-situ compaction, is a method of casting near net shape ... This approach has led to a reduction in the number of melt related defects (pores, inclusions, etc.), a finer average grain ...
Polycrystalline casts tend to have higher fracture resistance, while monocrystalline casts have higher creep resistance. Jet ... The porosity between the columns is critical to providing strain tolerance (via a very low in-plane modulus), as it would ... In pure Ni3Al phase atoms of aluminium are placed at the vertices of the cubic cell and form the sublattice A. Atoms of nickel ... reduced defects, and increased the strength and temperature capability of the material. Modern superalloys were developed in ...
Sialon (Silicon Aluminium Oxynitride) has high strength; resistance to thermal shock, chemical and wear resistance, and low ... The glass is shaped when either fully molten, by casting, or when in a state of toffee-like viscosity, by methods such as ... Later ceramics were glazed and fired to create smooth, colored surfaces, decreasing porosity through the use of glassy, ... The microstructure includes most grains, secondary phases, grain boundaries, pores, micro-cracks, structural defects and ...
Nickel content offsets brittleness induced by diffusion of aluminium when brazing aluminium-containing alloys, e.g. aluminium ... Cast iron "welding"[edit]. The "welding" of cast iron is usually a brazing operation, with a filler rod made chiefly of nickel ... The steam bubbles exert high pressure in the metal structure, leading to cracks and joint porosity. Oxygen-free copper is not ... Silver bracing may cause defects in certain alloys, e.g. stress-induced inter-granular cracking in copper-nickel. ...
It also increases porosity due to beneficial defects, creating buoyancy and reusability. Iron, in the form of ferrocene makes ... Nanowires in turn can be used to cast nanotubes of other materials, such as gallium nitride. These can have very different ... comparable to more expensive aluminium-lithium alloys.[2] ... structured pores and the porosity can be tailored for specific ... For this, vias comprising tightly packed (,1013 cm−2) metallic CNTs with low defect density and low contact resistance are ...
... which can cause fusion defects, porosity, and weld metal embrittlement if they come in contact with the electrode, the arc, or ... refractory aluminium oxide (sapphire) layer that forms on aluminium metal within minutes of exposure to air. This oxide layer ... such as the use of a nickel filler metal for joining steel and cast iron). Very different materials may be coated or "buttered ... Due to porosity problems in ferritic steels and limited benefits, however, it is not a popular shielding gas additive.[31] ...
Marine Aluminium Aanensen subsequently merged with Hydro Aluminium Maritime to become Hydro Marine Aluminium. Some of these ... "A flow-partitioned deformation zone model for defect formation during friction stir welding". Scripta Materialia. 58: 372-376. ... Issues such as porosity, solute redistribution, solidification cracking and liquation cracking do not arise during FSW. In ... The centre tunnel of the Ford GT is made from two aluminium extrusions friction stir welded to a bent aluminium sheet and ...
... from the sintering of high purity nanoparticles and powders-include microstructural defects such as residual porosity and grain ... Aluminium oxynitride spinel[edit]. Aluminium oxynitride spinel (Al23O27N5), abbreviated as AlON, is one of the leading ... and slip casting.[22] ... In addition to porosity, most of the interfaces or internal ... The key to this method is to keep porosity intergranular during pre-sintering, so that it can be removed subsequently by HIP ...
Hydrogen gas porosity Inclusions in aluminium alloys Non-metallic inclusions for inclusions in steel Porosity sealing Rao 1999 ... Closed shrinkage defects, also known as shrinkage porosity, are defects that form within the casting. Isolated pools of liquid ... A casting defect is an undesired irregularity in a metal casting process. Some defects can be tolerated while others can be ... The following defects can occur in sand castings. Most of these also occur in other casting processes. Shrinkage defects can ...
Hydrogen gas porosity is an aluminium casting defect under the form of a porosity or void in an aluminium casting caused by a ... Hydrogen causes porosity in aluminum products leading to many casting defects, reduced mechanical properties like fatigue and ... Because the solubility of hydrogen in solid aluminium is much smaller than in liquid aluminium, when the aluminium freezes, the ... Aluminum smelters and aluminum foundries want to produce high quality aluminum and shape castings with minimum porosity. This ...
Shrinkage porosity is one of the most common defects leading to rejection of aluminium die casting, often only showing up after ... The die casting part product of this study is provided through aluminium die casting factory, so the casting body no changes. A ... However, with large structural castings, defect analysis of this study focuses on maximum porosity in the selection casting, ... The final MVLR model equation for porosity after substituting regression coefficients is as follows: ...
The main types are: gas porosity, shrinkage defects, mold material defects, pouring metal defects, and metallurgical defects. ... The process is easily automated and more precise than sand casting. Common metals that are cast include cast iron, aluminium, ... Defects[edit]. Main article: Casting defects. There are a number of problems that can be encountered during the casting process ... Sand casting[edit]. Main article: Sand casting. Sand casting is one of the most popular and simplest types of casting, and has ...
... technique produces wheels that are totally free from the defects and porosity that can always occur in conventional casting ... Inertia is therefore also 25% lower than with cast aluminium alloy wheels. Almost maniacal care has been taken over the RSV ... In line with Aprilia practice, the frame incorporates aluminium-silicon castings and Peraluman 450 pressings. The frame has ... Each wheel weighs about 25% less than the lightest available wheels made using conventional aluminium casting techniques. ...
entrained inclusions, aluminium casting, porosity, hydrogen. Research Area:. Mechanical, aeronautical and manufacturing ... This defect not only acts as a crack but also it is recognized to initiate hydrogen porosity in the solidified casting, which ... El-Sayed, M. A., Hassanin, Hany and Essa, Khamis (2016) Bifilm defects and porosity in Al cast alloys. The International ... In this work, a casting from an A356 Al alloy was allowed to solidify under vacuum. The solidified casting was sectioned into ...
... hardened aluminium alloy component, comprising the steps of: a) depositing by cold spray on said component to be repaired a ... The invention refers to a method for the repair of an aluminium alloy component, in particular a precipitation- ... Cold deposition repair of casting porosity US20090260724A1 (en) * 2008-04-18. 2009-10-22. United Technologies Corporation. Heat ... The test pieces with simulated defect were repaired by means of cold spray by depositing a layer of 357 aluminium alloy powder ...
Defects such as casting porosity are made more evident! This can be advantageous in identifying faulty jewellery. ... For cyanide solutions, the gold can be precipitated by additions of zinc or aluminium dust. ... Defects to be avoided include casting porosity, inclusions and embedded polishing compounds, scratches and tool marks, and ... It will remove very small defects (1-2 microns) but not larger defects. ...
... dendrite arm spacing function automatically measures the mean secondary dendrite arm spacing in lightweight aluminium casting ... Enhanced ability to measure simple and complex porosity means that users can be confident in their weld assembly and additive ... It also supports various illumination methods, including MIX observation, which enables users to highlight defects and ...
... castings and welds; segregation, porosity and eutectic solidification). Metallographic and analytical techniques (diffraction, ... Welding of carbon steels, stainless steels, aluminium and aluminium alloys. Development and qualification of welding procedure ... Subsolidus reactions and defects in minerals (thermodynamic basis, defects, importance of subsolidus reactions). Classification ... Liquid metal processing (casting processes, solidification of castings and mould design). Deformation processing (forging, ...
The continuous casting process is also used in the production of cast iron, aluminium and copper alloys. ... A defect appearing as a seam on a rolled bar. Laps are rolled over pieces of material that arise when a bar is given a pass ... A method for detecting surface porosity or cracks in metal. The part to be inspected is cleaned and coated with a dye which ... Cast Iron. A definition can be applied that Cast Iron is an alloy of iron and carbon in which the carbon is in excess of the ...
Buy the Hardcover Book Refractories for Aluminium by Andrey Yurkov at Indigo.ca, Canadas largest bookstore. + Get Free ... Some words about quality control 1.2 Density, porosity and related characteristics. The types of porosity. 1.3 Mechanical ... 2.3.2 Elements of technology, raw materials and processing 2.3.3 Defects in carbon cathode blocks 2.3.4 Testing and ... 3.1 Cast house 3.2 3.2 Physical and chemical interaction of refractories with aluminium and aluminium alloys 3.3 Refractories ...
Porosity in Welding - Defects / Imperfections in Welds - Surface coatings like primer paints and surface treatments such as ... Optimizing the Heat Treatment Process of Cast Aluminium Alloys - Optimizing the Heat Treatment Process of Cast Aluminium Alloys ... Die casting surface treatments: avoiding blisters, pitting Among the most widespread defects in die casting surface treatments ... Tooling for Die Casting__. Tooling for Die Casting 12 Checklist for Die Casting Die Specifications To be used in consultation ...
Forde, John (2015) The elevated temperature performance of cast aluminium alloys and the development of a cast aluminium-copper ... Chen, Qi (2017) The effect of transition metal additions on double oxide film defects in al alloy castings. Ph.D. thesis, ... Campbell, John (1967) Origin of porosity in cast metals. Ph.D. thesis, University of Birmingham. ... Yue, Yang (2014) Modelling of the effects of entrainment defects on mechanical properties in Al-Si-Mg alloy castings. Ph.D. ...
Porosity is also often found out after machining operations. This work proposes non-destructive methods of castings inspection ... Prešov, Adin, [3] WALKINSON, W. G. Die Casting Defects-Causes and Solutions. Rosemont: NADCA, [4] BOLIBRUCHOVÁ, D. - KANTORÍK, ... In: Konference Aluminium [Sborník.]. Košice : s ISSN [2] MICHNA, Š.: Encyklopedie hliníku. ... CASTING HAND PRODUCTION USING MOULDS Second School Year CASTING HAND PRODUCTION USING MOULDS 1. Casting Casting is a production ...
This study aims to evaluate the effect of grain refinement on slurry formation and surface segregation in semi-solid castings ... and to cast complex shaped castings with less defects compared to coarser microstructures. The addition of grain refiners to ... Grain refinement is commonly used in the aluminium casting industry.[1] Smaller and more globular crystals form in grain- ... a decreased hot tearing tendency and more uniform dispersion of porosity and intermetallic phases.[2,3] Additionally, improved ...
... ranging in size from aluminium compressor discs to stainless steel or cast iron housings, from a number of different sources. " ... Combined NDT defect analysis and dimensional inspection It is in the new Technical Centre in Poland that the Nikon Metrology XT ... The electron beam weld that joins the impeller to the shaft can be inspected to check for porosity and mechanical integrity, a ... In castings, for example, it is possible to ascertain the location and size of a void or crack emanating from it and determine ...
Other possible defects are gas porosity, shrinkage porosity, hot tears, and flow marks. Flow marks are marks left on the ... ferrous die casting is also possible.[6] Specific die casting alloys include: zinc aluminium; aluminium to, e.g. The Aluminum ... See also: Casting defect. After the shakeout of the casting it is inspected for defects. The most common defects are misruns ... When no porosity is allowed in a cast part then the pore-free casting process is used. It is identical to the standard process ...
The thin paint like coatings are unlikely to give full protection due to defects and the most dependable barrier linings are ... Melt processed polymers such as PVDF, PFA and ETFE are preferred to PTFE due to its inherent porosity. ... Materials suitable for liquid oxygen service are nickel steel, austenitic stainless steels, and copper or aluminium alloys. ... Specially developed stainless steels have replaced traditional cast iron applications for high temperature duties. ...
The sound butt joints which were free from brazing defects such as porosity and lack of penetration could be obtained at the ... Dies for die casting are made of quality steels and are of very complex shape. As far as their repair is concerned this means ... particularly aluminium, magnesium and their alloys). The first part describes a suitable laser unit enabling crack grooving and ... Abstract: The paper treats the application of laser to repair of cracks occurring at dies for die casting of non-ferrous metals ...
The students will be able to understand the various processes for sealing porosity in badly made castings and to appreciate ... The students should be able to diagnose the major defects in castings and propose methods of preventing them. Basic knowledge ... general background information about aluminium is needed as an introduction of other subject areas of aluminium application ... TALAT Lecture 3207: Solidification Defects in Castings. This lecture provides an introduction to the causes and remedies of the ...
Depth of surface defects. *Porosity content. Corrosion Testing. Oxalic Acid Test, ASTM A 262, Practice A * Ferric Sulfate - ... Graphite type and distribution in cast irons. *Segregation of carbides 2. On non-ferrous alloys *Grain size ...
How to get glossy finish on Aluminium Pressure Die cast products by Shot Blasting?. 56278. Seeking to restore anodized truck ... Hard Anodizing Defect: "granulation" 56190. Need NiCr plated onto substrate. 56191. Plating onto hard chrome. 56192. Procedure ... High phosphorous electroless nickel has poor salt spray life due to base metal porosity. 56121. Our nickel plating is white and ... Chrome Coating Over Cast Steel. 56681. Zinc castings, food safe? dishwasher safe?. 56682. A student question on tin ...
Manufacturing defects found in cast wheels include cavities or porosity and a different metallurgical microstructure, entailing ... With its own in-house magnesium foundry, Marvic makes cast and forged magnesium wheels (as well as forged aluminium). The ... And although cast wheels are more affordable than forged wheels, cast wheels are heavier than forged wheels for a given ... Cast magnesium wheels. Taking into account their generally inferior quality compared to forged wheels, the main advantage of ...
For example, in the case of casting metal components, defects are often encountered in the form of shrinkage porosity. These ... The metal powder may be selected from the group consisting of nickel, cobalt, titanium, iron, aluminium and alloys thereof. The ... porosity. Percentage porosity may be considered (total volume of voids/ total volume) x100. In other words the porosity of the ... HIP processing of cast parts has been shown to successfully reduce such shrinkage porosity, thus improving the integrity of the ...
  • Surface voids (small holes, also known as bug holes or pitting) found on the surface of concrete castings have affected anyone who has ever cast concrete. (thealphagames.eu)
  • Forging products are consistent, without the defects of porosity, inclusion or voids, and finishing operations like machining, coining, sizing, straightening or surface treatments can also be easily done. (niir.org)
  • The CT capability enables 3 dimensional reconstructions of specimens to be created that can show the full extent of voids, cracks and other casting defects as well as their exact location. (axt.com.au)
  • Some words about quality control 1.2 Density, porosity and related characteristics. (indigo.ca)
  • Hot Isostatic Pressing (HIP) is a process that can be used to density powders, cast parts or sintered parts at high pressure and high temperatures. (sumobrain.com)
  • To enhance the catalytic properties, high energy mechanical milling was performed to increase the surface area and defect density. (unt.edu)
  • 06-20 Wei Xing, Di Ouyang, Zhen Chen and Lin Liu, Effect of energy density on defect evolution in 3D printed Zr-based metallic glasses by selective laser melting , Science China Physics, Mechanics & Astronomy, 63, art. (flow3d.com)
  • Pressure casting of full solid spheres of Al2O3 with 60 mm dia and 60% green density is achieved successfully. (arci.res.in)
  • A unique structure of the achieved composite materials, together with good mechanical properties and abrasive wear resistance at low density, ensured by an aluminium alloy matrix, are indicating broad application possibilities of such composites. (intechopen.com)
  • 2.3.2 Elements of technology, raw materials and processing 2.3.3 Defects in carbon cathode blocks 2.3.4 Testing and characterization 2.3.5 Some words on grades of carbon cathode blocks 2.3.6 Some words on structure of carbon cathode blocks in connection with grain size composition, sintering and pore size structure 2.3.7 Interaction of carbon cathode blocks with the steel shell and the collector bars. (indigo.ca)
  • The present invention relates to a method for manufacture of alumina ceramic tubular symmetric micro-filtration (MF) single or multi-channeled membranes with versatility in geometry / profile i.e., single or multi-channeled hollow or any other profile and variable physical dimensions e.g., length, internal diameter (ID), outer diameter (OD), channeled-diameter (CD) etc., with consistent pore size, porosity, mechanical strength and chemical stability. (allindianpatents.com)
  • Importantly, multiple pore size distribution, interconnected pore structure and high porosity of scaffolds will facilitate vascularization and diffusion of nutrients and gases. (royalsocietypublishing.org)
  • Quantity of porosity along with the tailored pore size becomes critical to choose an optimum as these properties conflicts each other. (arci.res.in)
  • If liquid aluminium entered a mould cavity with a velocity greater than a critical value, the surface skin of the liquid metal would fold over onto itself and be submerged into the bulk liquid with a volume of air entrapped within it, creating what is called a bifilm defect. (kingston.ac.uk)
  • Rhodium is often used to give a good white colour to white gold jewellery (which is often not a good white colour) or is used selectively on yellow gold jewellery to give local areas of whiteness, often around gem stone settings, and also to plate the master model made in silver used for making the rubber mould in investment casting. (ganoksin.com)
  • Casting process involves melting the metal to be used, pouring it into a mould, letting it cool and then knocking out the casting. (niir.org)
  • Three of the castings were produced in small moulds with natural cooling, forced cooling and insulated conditions and one casting was made in a large mould with natural cooling. (ubc.ca)
  • Polymer moulds prepared to pressure cast shapes like spools, solid spheres, one end closed tubes and successfully used on the PCM with Al2O3 slips. (arci.res.in)
  • Porous skeletons made of Al2O3 aluminium are sintered reactively using blowing agents or are manufactured by ceramic injection moulding (CIM) from powder. (intechopen.com)
  • 04-20 Santosh Reddy Sama, Tony Badamo, Paul Lynch and Guha Manogharan, Novel sprue designs in metal casting via 3D sand-printing , Additive Manufacturing, 25, pp. 563-578, 2019. (flow3d.com)
  • Gas porosity is the formation of bubbles within the casting after it has cooled. (wikipedia.org)
  • If neither of these are the case then most likely the porosity is due to gas formation. (wikipedia.org)
  • This study aims to evaluate the effect of grain refinement on slurry formation and surface segregation in semi-solid castings produced by the Rheometal™ process. (springer.com)
  • 11 ] studied defect bands and surface segregation layer formation in HPDC and suggested, in addition to the migration of the externally solidified crystals to the center, that the origin of the segregation layer is a combined effect of inverse segregation and exudation. (springer.com)
  • Ideal selectivities lower than Knudsen selectivities were obtained as a result of defects from intercrystalline slits and crack formation during synthesis and template removal. (scielo.org.za)
  • Porosity was observed and is discussed here in terms of its mechanism of formation. (go.jp)
  • The FSW process takes place in the solid- phase, at temperatures below the melting point of the material, and as a result does not experience problems related to formation of porosity, and cracks. (ijert.org)
  • The tool must perform many functions, including generating heat, promoting mixing, breaking up the joint line, creating forging pressure, and preventing the formation of defect. (ijert.org)
  • Die casting is a metal casting process that is characterized by forcing molten metal under high pressure into a mold cavity . (wikipedia.org)
  • Magnesium wheels are produced either by casting (metalworking) (where molten metal is introduced into a mold, solidifying within the mold), or by forging (where a prefabricated bar is deformed mechanically). (autosystempro.com)
  • Alumina Ceramic foam Filter is developed as a new type molten metal filters to decrease casting flaw in recent years. (made-in-china.com)
  • Foamed ceramics have the characters of light weight, high mechanical strength, large specific surface areas, high porosity, excellent thermal shock resistance, chemical corrosion resistance and high temperature stability in molten metal. (made-in-china.com)
  • In general, almost all of the solid impurities are oxides and the like incorporated in molten metal to be used in the production of cast product. (google.com)
  • Since the metal cast product has usually been produced by filtering a melt of fresh metal, there has hitherto been practised a method of filtering solid impurities by passing molten metal through a bed filter made, for example, of alumina balls with a diameter of several millimeters or alumina sintered body. (google.com)
  • There are many types of defects which result from many different causes. (wikipedia.org)
  • This basic principle can be exploited to create a microwave NDT system, which allows localizing and classifying various types of defects within DUTs. (ndt.net)
  • However, SSM cast components tends to contain residual porosity, which is extremely detrimental to performance. (dcu.ie)
  • 10 Although aluminium-free mordenite framework inverted (MFI or silicalite-1) and deca-dodecahedra rhombohedral type zeolites are able to separate molecules by size, these membranes are still not effective as a result of residual defects remaining in the separation layer. (scielo.org.za)
  • Recently it has been shown that intercrystalline defects were present even in alumina-free MFI membranes where the size of the defects was determined by adsorbing gas (i-butane, p-xylene and benzene) onto the membrane layer. (scielo.org.za)
  • Traditional ceramic raw materials include clay minerals such as kaolinite , whereas more recent materials include aluminium oxide, more commonly known as alumina . (explained.today)
  • K. Heim, G. S. Vinod-Kumar, F. García-Moreno, A. Rack, J. Banhart, Stabilisation of aluminium foams and films by the joint action of dispersed particles and oxide films, Acta Mater. (sciencepublishinggroup.com)
  • Gas porosity can sometimes be difficult to distinguish from microshrinkage because microshrinkage cavities can contain gases as well. (wikipedia.org)
  • Modern scientific and engineering developments led to significant improvements in magnesium wheels qualities, including high-tech anti-corrosion treatment that extends the lifecycle of a wheel to match or even exceed the lifecycle of comparable aluminium alloy wheel. (autosystempro.com)
  • In the current study of die casting for Automobile starter motor casing, the following issues are focused: shot piston simulation, defect analysis, and, finally, the use of the Taguchi multiquality analytical method to find the optimal parameters and factors to increase the aluminium ADC10 die casting quality and efficiency. (hindawi.com)
  • The high power (450 kV) X-ray equipment is able to penetrate the dense materials used in turbocharger production, allowing the internal material quality of castings to be checked non-destructively and the integrity of welded assemblies to be inspected. (ndt.net)
  • In castings, for example, it is possible to ascertain the location and size of a void or crack emanating from it and determine the likely cause of the fault and whether it is due to the type or quality of the material or the component design. (ndt.net)
  • This lecture provides an introduction to some of the finer points in the production of high quality castings. (nottingham.ac.uk)
  • Taking into account their generally inferior quality compared to forged wheels, the main advantage of cast wheels is the relatively low cost of production. (autosystempro.com)
  • Therefore, it is necessary to use cast products of high quality for the manufacture of such metal thin sheets and wires and as a result, solid impurities causing the above defects should be completely removed from the cast product. (google.com)
  • This combination generates brilliant image quality with excellent contrast to quickly and easily reveal defects and flaws. (axt.com.au)
  • The authors report that the effectiveness of the rotary degassing process is highly dependent on the combination of rotational speed and the gas flow rate, and that a wrong combination of these factors may result in no improvement or even degradation in the quality of castings. (scirp.org)
  • Other topological defects induce the polymerization of tubes and creation of 'Y', 'T' and 'X' nanotube junctions. (spie.org)
  • Based on calcium phosphate (Ca-P)/poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) nanocomposite microspheres, three-dimensional Ca-P/PHBV nanocomposite scaffolds with customized architecture, controlled porosity and totally interconnected porous structure were successfully fabricated using selective laser sintering (SLS), one of the rapid prototyping technologies. (royalsocietypublishing.org)
  • The redistribution of solute in the castings has been evaluated using a novel image processing technique based on the area fraction of silicon. (ubc.ca)
  • 3. The composition of claim 1 , wherein the solid polymeric biodegradable material comprises a biologically compatible salt whose particle size alters the porosity of the polymeric biodegradable material. (google.com)
  • For casting that are a few kilograms in weight the pores are usually 0.01 to 0.5 mm (0.00039 to 0.01969 in) in size. (wikipedia.org)
  • Not only does this method allow manufacturers to create products at a low cost, but there are other benefits to sand casting, such as very small-size operations. (wikipedia.org)
  • The flexural strength of brittle materials is limited by the number of defects beyond a specific size. (afcarbide.de)
  • A volume correlation does exist, as the probability of finding a defect increases with the size of the sample. (afcarbide.de)