Cast cobalt alloys were developed to bridge the gap between high-speed steels and carbides. Although comparable in room-temperature hardness to high-speed steel tools, cast cobalt alloy tools retain their hardness to a much higher temperature and can be used at higher cutting speeds than high-speed steel tools. This article provides an overview of the processing, properties, and applications of these alloys.

This article discusses the physical metallurgy of cast cobalt alloys with an emphasis on the crystallography, compositions, phases and microstructure, and properties. Cobalt alloys are cast by several different foundry methods. The article describes the argon-oxygen decarburization and continuous casting process. It provides information on castability and quality of the casted alloys. The article details the postcasting treatment, including heat treatment, hot isostatic pressing, and coatings. It summarizes the applications of cast cobalt alloys.

This article reviews the concepts considered important for an understanding of the processes used for preparing cobalt-chromium alloy implants, the microstructures resulting from this processing, and the resulting material properties. The review includes solidification of alloys, diffusionless (martensitic) phase transformation as occurs with face-centered cubic to hexagonal close-packed transformation in cobalt-chromium alloys, and stacking faults and twins and their role in this transformation. It also discusses the strengthening mechanisms that are responsible for the mechanical properties of cast and wrought cobalt alloys. The article contains tables that list the commonly used cobalt alloys and their biomedical applications and chemical compositions. It discusses the mechanical and corrosion properties of cobalt alloys, and provides a description of the microstructure of cobalt alloys.

Cobalt finds its use in various applications owing to its magnetic properties, corrosion resistance, wear resistance, and its strength at elevated temperatures. This article discusses the mining and processing of cobalt and cobalt alloys. It describes the types of cobalt alloys, including wear-resistant alloys, high-temperature alloys, corrosion-resistant alloys, and special-purpose alloys. The article provides data on the chemical composition, mechanical properties, and physical properties of these alloys. Further, it provides information on the uses of cobalt in superalloys, cemented carbides, magnetic materials, low-expansion alloys, and high-speed tool steels.

Cobalt is used as an alloying element in alloys for various applications. This article provides a detailed account of the metallurgy of cobalt-base alloys. It focuses on the compositions, properties, and applications of cobalt-base alloys, which include wear-resistant cobalt alloys, heat-resistant cobalt alloys, and cobalt-base corrosion-resistant alloys. The article also describes the heat treatments such as annealing and aging, for these alloys.

This article provides a general overview of physical and mechanical properties, alloy compositions, applications, and product forms of cobalt-base alloys as wear-resistant, corrosion-resistant, and/or heat-resistant materials. The discussion is largely focused on cobalt-base alloys for wear resistance, as this is the single largest application area of cobalt-base alloys.

This article describes the metallurgy and microstructure of high-performance cobalt-base alloys. It discusses metallographic preparation procedures, including sectioning, mounting, grinding, polishing, etching, staining, and heat tinting. It examines the microstructure of cobalt alloys in cast, wrought, and powder metal forms, including magnetic alloys as well as several cobalt-base superalloys.

This article addresses the cobalt and cobalt-base alloys most suited for aqueous environments and those suited for high temperatures. The performance of cobalt alloys in aqueous environments encountered in commercial applications is discussed. The article provides information on the environmental cracking resistance of the cobalt alloys. Three welding processes that are used for hardfacing with the high-carbon Co-Cr-W alloys, namely, oxyacetylene, gas tungsten arc, and plasma-transferred arc are also discussed. The article examines the effects of various modes of high-temperature corrosion. It describes the applications and fabrication of cobalt alloys for high-temperature service.

This article discusses the classifications of high-speed tool steels and describes alloying elements and their effects on the properties of high-speed tool steels. It analyzes the heat treatment of high-speed tool steels, namely, preheating, austenitizing, quenching, and tempering. Surface treatments for the high-speed tool steels are reviewed. The article emphasizes the properties and applications of high-speed tool steels and provides information on the factors in selecting high-speed tool steels.

This article focuses on the tribological behavior of group 1, 2, and 3 cobalt-base alloys, namely, carbide-type wear-resistant alloys and laves-type wear-resistant alloys. The behavior includes hardness, yield strength and ductility, and fracture toughness. The article contains a table that lists the nominal compositions and typical applications of cobalt-base alloys. It discusses the properties and relative performance of specific alloys when subjected to the more common types of wear. These include abrasive wear, high-temperature sliding wear, rolling-contact fatigue wear, and erosive wear.