This article describes dental alloy compositions and its properties. It discusses the safety and efficacy considerations of dental alloy devices. The article defines and compares interstitial fluid and oral fluid environments. Artificial solutions developed for the testing and evaluation of dental materials are summarized. The article examines the effects of restoration contact on electrochemical parameters and reviews the concentration cells developed by dental alloy-environment electrochemical reactions. The composition and characterization of biofilms, corrosion products, and other debris that deposit on dental material surfaces are discussed. The article evaluates the types of alloys available for dental applications, including direct filling alloys, crown and bridge alloys, partial denture alloys, porcelain fused to metal alloys, wrought wire alloys, soldering alloys, and implant alloys. The effects of composition and microstructure on the corrosion of each alloy group are also discussed. The article concludes with information on the tarnishing and corrosion behavior of these alloys.

Tin is a soft, brilliant white, low-melting metal that is most widely known and characterized in the form of coating. This article discusses the primary and secondary production of tin and explains the uses of tin in coating, namely tinplating, electroplating, and hot dip coatings. It presents a short note on pure (unalloyed) tin and uses of tin in chemicals. The article also covers the compositions and uses of tin alloys which include solders, pewter, bearing alloys, alloys for organ pipes, and fusible alloys. It goes on to discuss the other alloys containing tin including battery grid alloys, type metals, copper alloys, dental alloys, cast irons, titanium alloys, and zirconium alloys. Finally, it presents a short note on the applications of tin powder and corrosion resistance of tin.

This article focuses on the use of noble and precious metals for biomedical applications. These include gold, platinum, palladium, ruthenium, rhodium, iridium, and osmium. The physical and mechanical properties of noble and precious metals are presented in tables. A brief discussion on the ancient history of noble and precious metal use in dentistry is provided. The article discusses the use of direct gold dental filling materials, direct silver dental filling materials, traditional amalgam alloys, high-copper amalgam alloys, and gallium alloys in biomedical applications. It also provides information on gold coatings and iridium oxide coatings for stents.

Precious metals are of inestimable value to modern civilization. This article discusses the resources and consumption, trade practices, and special properties of precious metals and its alloys, including ruthenium, rhodium, palladium, silver, osmium, iridium, platinum, and gold, and tabulates the industrial applications of precious metals. It provides information on the commercial forms (wire, rod, sheet, strip, ribbon, and foil) and uses of precious metals, including semifinished products, precious metal powders, industrial uses, coatings, and jewelry.

Biomaterials are the man-made metallic, ceramic, and polymeric materials used for intracorporeal applications in the human body. This article primarily focuses on metallic materials. It provides information on basic metallurgy, biocompatibility, chemistry, and the orthopedic and dental applications of metallic biomaterials. A table compares the mechanical properties of some common implant materials with those of bone. The article also provides information on coatings, ceramics, polymers, composites, cements, and adhesives, especially where they interact with metallic materials.

Traditional processing methods for the part production of Co-Cr alloys include casting, powder metallurgy, and metal forming. However, the steps involved during materials processing followed by metal forming and machining are time consuming and fraught with processing variables. Three-dimensional (3D) printing enables rapid evolution in design, personalization, and so on. This article presents a brief description of some common additive manufacturing (AM) processes for the production of cobalt alloy parts, and provides a comparison between AM and conventional processing methods. The discussion is centered on process-microstructure-properties correlation in additively manufactured cobalt alloys and applications of these alloys.

This article provides information on biomedical aspects such as active biological responses and the chemical environment characterizing the internal physiological milieu, as well as electrochemical fundamentals needed for characterizing corrosion fatigue (CF) and stress-corrosion cracking (SCC). It discusses some of the mechanical and electrochemical phenomena related to the in vivo degradation of materials used for biomedical applications. These materials include stainless steels, cobalt and titanium-base alloy systems, and dental amalgam. The article addresses key issues related to the simulation of the in vivo environment, service conditions, and data interpretation. The factors influencing susceptibility to CF and SCC are reviewed. The article describes the testing methodology of CF and SCC. It also summarizes findings from laboratory testing, in vivo testing and retrieval studies related to CF and SCC.

This article focuses on the use of indium and bismuth in low-melting-temperature solders and fusible alloys. It describes how the two elements typically occur in nature and how they are recovered and processed for commercial use. It also provides information on designations, classification, composition, properties (including temperatures ranges), and some of the other ways in which indium and bismuth alloys are used.

Precious metals include gold, silver, and six platinum-group metals, namely, platinum, palladium, ruthenium, rhodium, osmium, and iridium. This article focuses on the consumption, trade practices, properties, product forms, and applications of these metals and their alloys.

This article discusses the chemical composition, fabrication characteristics, applications, mechanical properties, mass characteristics, thermal properties, electrical properties, optical properties, and chemical properties of precious metals, namely, silver, gold, platinum, and palladium and their corresponding alloys.

Superalloys are nickel, iron-nickel, and cobalt-base alloys generally used for high-temperature applications. Superalloys are used in aircraft, industrial, marine gas turbines, nuclear reactors, spacecraft structures, petrochemical production, orthopedic and dental prostheses, and environmental protection applications. This article discusses the material characteristics, phases, structures, and systems of superalloys. It describes the processing of superalloys, including primary and secondary melting, deformation processing (conversion), powder processing, investment casting, and joining methods. The article also describes the properties, microstructure, and thermal exposure of superalloys. It further discusses the effects of environmental factors on superalloys, including oxidation and hot corrosion. Protective coatings are also discussed. The article provides information on the mechanical properties and chemical composition of nickel, iron, and cobalt-base superalloys in both the cast and wrought forms.

This article provides a summary of the concepts discussed in the Section “Corrosion in Specific Industries” in the ASM Handbook, Volume 13C:Corrosion: Environments and Industries. This Section applies the fundamental understanding of corrosion and knowledge of materials of construction to practical applications. The industries addressed are nuclear power, fossil and alternative fuel, land transportation, air transportation, microelectronics, chemical processing, pulp and paper, food and beverage, pharmaceutical and medical technology, petroleum and petrochemical, building, and mining and metal processing.

This article describes the corrosion resistance and ion release from main transition metallic bearings used as medical devices. It discusses the main issues associated with the in vivo presence of ions and their biocompatibility during the exposure of patients to different aspects of ion toxicity. These include ion concentration and accumulation in organisms, reactive oxygen species and oxidative stress, and carcinogenicity stimulated by the corrosion process and toxic ions release.

Tin is produced from both primary and secondary sources. This article discusses the chemical compositions, production, properties, microstructure and applications of tin and tin alloys. The major tin alloys discussed here are tin-antimony-copper alloy (pewter), bearing alloy, solder alloy and other alloys containing traces of tin. Data on tin consumption in the United States is presented graphically.

This article reviews friction and wear of various dental materials that have been studied by fundamental wear measurements, simulated service wear measurements, and clinical measurements. The materials include dental amalgam, composite restorative materials, pit and fissure sealants, dental cements, porcelain and plastic denture teeth, dental feldspathic porcelain and ceramics, endodontic instruments, periodontal instruments, and orthodontic wires. The article describes the correlations of properties such as the hardness, fracture toughness, and wear. It provides information on wear mechanism such as the sliding adhesive wear, two-body abrasion, three-body abrasion, erosion, and fatigue.

The additive manufacturing technologies in the casting of precious metals are divided into two groups: indirect metal methods and direct metal methods. Besides providing a process overview of both of these methods, the focus of this article is on the characteristics, process steps, applications, and advantages of direct metal methods, namely laser melting, material extrusion, binder jetting, material jetting, and vat photopolymerization methods.

Copper, copper alloys, and precious metals are probably the most easily brazed metals because of their resistance to oxidation at high temperatures. This article provides a brief discussion on the metallurgy of copper, copper alloys, and precious metals and discusses the filler metals, brazing fluxes, joint clearance and design, and different brazing processes used in brazing of copper, copper alloys, and precious metals.

The human internal environment plays a vital role in the friction and wear of implants and prosthetic devices. This article describes the tribological/wear behavior of implants. It discusses the classification of active tribological pairs, namely, amphiarthosis joints and diarthosis joints. The article details the classification of total knee replacement, depending on the type of mechanical stability, including nonconstrained knee replacement, semiconstrained knee replacement, and constrained knee replacement. It also discusses the classifications of passive tribological pairs, namely, total disc replacement in the spine, dental implants, and temporomandibular joint. It describes the various testing methods for characterizing the implant materials used in hip, knee, spine, and dental applications. The article also describes the typical standards used for testing wear behavior of tribological pairs, namely, hip-wear simulation standards, knee-wear simulation standards, and spinal disc-wear simulation standards.

Stainless steels are used for medical implants and surgical tools due to the excellent combination of properties, such as cost, strength, corrosion resistance, and ease of cleaning. This article describes the classifications of stainless steels, such as austenitic stainless steels, martensitic stainless steels, ferritic stainless steels, precipitation-hardening stainless steels, and duplex stainless steels. It contains a table that lists common medical device applications for stainless steels. The article discusses the physical metallurgy and physical and mechanical properties of stainless steels. Medical device considerations for stainless steels, such as fatigue strength, corrosion resistance, and passivation techniques, are reviewed. The article explains the process features of implant-grade stainless steels, including type 316L, type 316LVM, nitrogen-strengthened, ASTM F1314, ASTM F1586, ASTM F2229, and ASTM F2581 stainless steels.

This article outlines the selection criteria for choosing an implant material for biomedical devices in orthopedic, dental, soft-tissue, and cardiovascular applications. It details the development of various implants, such as metallic, ceramic, and polymeric implants. The article discusses specific problems associated with implant manufacturing processes and the consequent compromises in the properties of functionally graded implants. It describes the manufacturing of the functionally-graded hip implant by using the LENS process. The article reviews four different types of tissue responses to the biomaterial. It discusses the testing methods of implant failure, such as in vitro and in vivo assessment of tissue compatibility.