This article describes the characteristics of tools and dies and the causes of their failures. It discusses the failure mechanisms in tool and die materials that are important to nearly all manufacturing processes, but is primarily devoted to failures of tool steels used in cold-working and hot-working applications. It reviews problems introduced during mechanical design, materials selection, machining, heat treating, finish grinding, and tool and die operation. The brittle fracture of rehardened high-speed steels is also considered. Finally, failures due to seams or laps, unconsolidated interiors, and carbide segregation and poor carbide morphology are reviewed with illustrations.

This article describes the effects of undissolved carbides formed by segregation of alloying elements on the hardness of the powder-metallurgical (PM) high-alloy tool steels (HATS). It explains the calculation of exact stoichiometric carbon content that depends on the required martensite hardness, amount of carbon forming alloying elements, types of undissolved carbides during austenitizing, and the densities of the carbides. Microhardness values for carbides in HATS are also listed.

This article describes procedures for producing powder metallurgy high-speed tool steel powder by inert-gas atomization, followed by compaction by hot isostatic pressing. These include the anti-segregation process (ASP) and the crucible particle metallurgy (CPM) process. The article reviews the properties of ASP and CPM and summarizes the procedures to heat treat ASP high-speed tool steels. It discusses the processing steps, advantages, and applications of the FULDENS process that uses water-atomized powders compacted by vacuum sintering. The article also provides information on the applications of tool steels.

From the point of view of economics and ecology, thin-wall ductile iron (TWDI) castings can compete in terms of mechanical properties with the light castings made of aluminum alloys. This article discusses the effect of technological factors on the cooling rate and physicochemical state of the liquid metal for preparing thin-wall castings with good mechanical properties and performance while avoiding casting defects. It describes a variety of defects that may appear during the production of TWDI castings, such as casting skin anomalies (e.g., flake graphite, graphite segregation), graphite clusters, exploded graphite, slag inclusions, shrinkage porosity, eutectic chill and secondary carbides, and cold shuts. The article reviews the tensile, fatigue, impact, and wear properties of TWDI castings. It provides information on the production and applications of TWDI castings.

This article focuses on the physical metallurgy of nonferrous high-temperature materials that affects weldability on the precipitates used for age hardening (strain-age cracking). Those precipitates associated with solidification and solidification segregation, primarily Laves and carbides (heat-affected zone grain boundaries cracking), are also discussed. The article examines the parameters that affect heat-affected zone liquation cracking and presents a solution for each problem.

Tool steels are prepared for metallographic examination in the same way as carbon steels with a few variations owing to hardness and alloying differences. This article explains what makes tool steels different and how to compensate for it when sectioning, mounting, grinding, polishing, and etching. It provides information and data on composition, hot working, austenitizing, tempering, and powder metal manufacturing and explains how it affects tool steel microstructure, using more than 100 detailed images.

Wrought powder metallurgy (P/M) high-speed tool steels exhibit better machinability, dimensional control and safety in heat treatment, grindability, and edge toughness during cutting. This article discusses the two stages of machining of P/M tool steels: rough machining, in annealed condition, and finish machining, in hardened-and-tempered condition. It tabulates the composition of commercial crucible particle metallurgy and anti-segregation process tool steels and their typical machining conditions.