This article briefly reviews the production methods and characteristics of plain carbon and low-alloy water-atomized iron and steel powders, high-porosity iron powder, carbonyl iron powder, and electrolytic iron powder. It emphasizes on atomized powders, because they are the most widely used materials for ferrous powder metallurgy. The article provides information on the properties and applications of these powders. It also includes an overview of diffusion alloying, basics of admixing, and bonded premixes.

This article describes the solid-phase and liquid-phase processes involved in diffusion bonding of metals. It provides a detailed discussion on the diffusion bonding of steels and their alloys, nonferrous alloys, and dissimilar metals. Ceramic-ceramic diffusion welding and a variation on this process in which ceramic powder compacts are simultaneously sintered and bonded are also discussed.

This article provides a qualitative summary of the theory of diffusion bonding, as distinguished from the mechanisms of other solid-state welding processes. Diffusion bonding can be achieved for materials with adherent surface oxides, but the resultant interface strengths of these materials are considerably less than that measured for the parent material. The article describes three stages of diffusion bonding: microasperity deformation, diffusion-controlled mass transport, and interface migration. It concludes with information on diffusion bonding with interface aids.

The goals of modeling diffusion bonding can be regarded as twofold: to optimize the selection of the process variables for a given material and to provide an understanding of the mechanisms by which bonding is achieved. This article describes the existing models of diffusion bonding with an assumption that the surfaces to be joined are free of contaminants and oxide, that bonding occurs between similar materials, and that the materials are single-phase metals. It discusses the mechanisms considered for diffusion bonding and limitations of existing models.

This article describes different types of titanium alloys, including alloy Ti-6Al-4V, alpha and near-alpha alloys, and alpha-beta alloys. It explains the formability of titanium alloys with an emphasis on the Bauschinger effect. The article provides information on the tool materials and lubricants used in the forming process. It provides information on the cold and hot forming, superplastic forming, and combination of superplastic forming/diffusion bonding. The article discusses the various forming processes of these titanium alloys, including press-brake forming, power (shear) spinning, rubber-pad forming, stretch forming, contour roll forming, creep forming, vacuum forming, drop hammer forming, joggling, and explosive forming.

This article discusses many of the processes and related considerations involved in the forming of superplastic sheet metal parts. It reviews the requirements for superplasticity and describes the characteristics of superplastic metals. The characterization of superplastic behavior includes the characterization of plastic flow, internal cavitation, and fracture behavior. Processing variables needed for the overall characterization of superplastic behavior are summarized. The article discusses the superplastic forming methods, namely, blow forming, vacuum forming, thermoforming, deep drawing, superplastic forming/diffusion bonding, forging, extrusion, and dieless drawing. It provides information on superelastic forming equipment and tooling. The article explains the thinning characteristics and quick plastic forming and its technological elements. It describes the manufacturing practice of the process. The article concludes with a discussion on the superplastic behavior in iron-base alloys.

This article describes the mechanism, advantages and disadvantages, fundamentals, capabilities, variations, equipment used, and weldability of metals in solid-state welding processes, including diffusion bonding, explosion welding, friction welding, ultrasonic welding, upset welding, and deformation welding.

Many applications of ceramics and glasses require them to be joined to each other or to other materials such as metals. This article focuses on ceramic joining technologies, including glass-metal sealing, glass-ceramic/metal joining, ceramic-metal joining, ceramic-ceramic joining, and the more advanced joining of nonoxide ceramics. It also discusses metallizing, brazing, diffusion bonding, and chemical bonding.

Diffusion bonding is only one of many solid-state joining processes wherein joining is accomplished without the need for a liquid interface (brazing) or the creation of a cast product via melting and resolidification. This article offers a qualitative summary of the theory of diffusion bonding. It discusses factors that affect the relative difficulty of diffusion bonding oxide-bearing surfaces. These include surface roughness prior to welding, mechanical properties of the oxide, relative hardness of the metal and its oxide film, and prestraining or work hardening of the material. The article describes the mechanism of diffusion bonding in terms of microasperity deformation, diffusion-controlled mass transport, and interface migration. It concludes with a discussion on diffusion bonding with interface aids.