Search Results for tool steels

This article provides a detailed discussion on various recommended heat treating practices, including normalizing, annealing, austenitizing, quenching, tempering, stress relieving, preheating, and martempering, for various low- and un-alloyed cold-work hardening tool steels. The steels discussed include water-hardening tool steels, shock-resisting tool steels, oil hardening cold-work tool steels, low-alloy special-purpose tool steels, and carbon-tungsten special-purpose tool steels.

This article focuses on various heat-treating practices, namely, normalizing, annealing, stress relieving, preheating, austenitizing, quenching, tempering, and nitriding for cold-work tool steels. The cold-work tool steels include medium-alloy air-hardening tool steels, high-carbon high-chromium tool steels, and high-vanadium-powder metallurgy tool steels. The article also describes the properties, types, nominal compositions and designations of these cold-work tool steels.

This article provides a discussion on heat treating practices, namely, carburizing, normalizing, annealing, stress relieving, preheating, austenitizing, quenching, tempering, and nitriding for various grades of mold and corrosion-resistant tool steels. It details the characteristics of various grades of mold and corrosion-resistant tool steels, including type P20, type P20Mod, AISI type 420, and AISI type 440B.

This article focuses primarily on the various steps involved in the brazing of heat-resistant alloys (nickel- and cobalt-base alloys). The major steps include the selection of brazing filler metals, surface cleaning and preparation, brazing processes and their corresponding atmospheres, and fixturing. The article also provides an overview of the brazing of blow-alloy steels and tool steels and oxide dispersion-strengthened alloys.

This article describes some of the underlying factors of tool steel and bearing steel fractures and appearances. It also briefly introduces the general types of cold work and hot work tool steels and their typical performance requirements. This includes the importance of microstructural conditions achieved with powder metallurgy (PM) tool steels and the need for steel “cleanliness,” especially in preventing contact fatigue in bearings or bending fatigue in gears.

The powder metallurgy (P/M) process has been used primarily for the production of advanced high-speed tool steels. However, the P/M process is also being applied to the manufacture of improved cold-work and hot-work tool steels. The basic heat treatments for P/M high-speed tool steels include preheating, austenitizing, quenching, and tempering. This article describes manufacturing properties, cutting tool properties, and applications of P/M high-speed tool steels. It discusses the development of P/M high-speed alloy steels that cannot be made by conventional methods because of their high carbon, nitrogen, or alloy contents. For high-speed tool steels, a number of important end-user properties have been improved by powder processing; machinability, grindability, dimensional control during heat treatment, and cutting performance under difficult conditions where high edge toughness is essential. Several of these advantages also apply to P/M cold- and hot-work tool steels, which, compared to conventional tool steels, offer better toughness and ductility for cold-work tooling, better thermal fatigue life, and greater toughness for hot-work tooling.

Tool steels are any steel used to make tools for cutting, forming, or shaping manufactured parts. Most tool steels are wrought products alloyed with relatively large amounts of tungsten, molybdenum, vanadium, manganese, and/or chromium. The article describes a wide variety of tool steels, including high-speed steels, hot and cold-work steels, shock-resisting steels, and special-purpose steels. Hot-work steels are designed to withstand excessive amounts of heat, pressure, and abrasion, suiting them for punching, shearing, and high-temperature forming applications. Cold-work tool steels have exceptional dimensional stability and wear resistance, but lack the alloy content necessary to resist softening at temperatures above 205 to 260 deg C. The article examines standard designations for all tool steel types and provides corresponding composition and property ranges. It also discusses surface treatments, fabrication issues, and in-service measures of performance.

Powder metallurgy (PM) high-alloy tool steels (HATS) have unique properties that assist them in solving various problems related to machining of metal components. This article describes the cost-intensive PM processing routes of HATS, as well as their major properties, including elastic properties, density, mechanical properties, grindability, fatigue and wear resistance, and thermophysical properties.

High-potential high-alloy tool steels (HATS) containing martensitic microstructure with undissolved hard phases are achieved by a number of complex heat treating cycles, predominantly tempering. This article focuses on three tempering treatments, namely, salt bath heat treatment, austenitizing, and vacuum heat treatment. It explains the result of these tempering processes with HSS M2 grade of HATS.

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 is a comprehensive collection of tables that list the nominal chemical composition of common powder metallurgy (PM) high-alloy tool steels, namely, PM high-speed, cold working, and corrosion-resistant tool steels.

The microstructure in the longitudinal direction of conventional high-alloy tool steels (HATS) depends very much on the degree of hot working. Comparing different processes, the highest processing temperature proves to be decisive for coarseness of the microstructure. This article provides a discussion on the microstructure of conventional HATS and hot isostatically pressed high-speed steel. The effects of the processing in cold worked HATS are illustrated.

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.

This article describes the selection of tool steels on the basis of specific product applications. It contains tables that list nominal speeds and feeds for the machining of various tool steels. The machining processes include turning, boring, broaching, drilling, reaming, tapping, milling, and sawing. The article explains the machining of the following tool steels: water hardening; types A, D and O cold-work; hot work; high speed, low-alloy special-purpose; and low-carbon mold. It details the machining of tool steel gears. The article also discusses the grinding of tool steels based on steel classification and the effects of steel composition and hardness on grindability. It reviews the types of grinding, namely, surface grinding, cylindrical grinding, centerless grinding, internal grinding, thread grinding, flute grinding, and low-stress grinding. Grinding of types-A, D, F, L, O, P, S and W steels, hot-work steels, and high speed steels, is also detailed.

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.

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 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.

Tool steels are an important class of steels due to their distinct applications and their specific heat treating issues. This article provides an overview of the classification and production of tool steels, and discusses the procedures and process control requirements for heat treating principal types of tool steels. It reviews the various heat treating processes, namely, normalizing, annealing, stress relieving, austenitizing, quenching, and tempering, and surface treatments and cold treating. The article also provides information on the applicability of these processes to various types of tool steels.

The design of a tool-steel part directly affects the susceptibility to shape distortion on heating and cooling. This article provides information on the selection of chemical composition and the effect of composition on size distortion. It explains the various factors considered to control distortion in tools steels, namely, design, initial condition, machining procedure, and heat treatment. Distortion can occur both during and after heat treatment. The article discusses the chief ways to precisely control the extent of distortion by heat treating and auxiliary mechanical methods. Stabilizing treatments, namely, stabilizing by tempering and stabilizing by cold treatment are used to minimize dimensional changes that occur following heat treatment.

Distortion, encompassing all irreversible dimensional changes, is of two main types: size distortion and shape distortion. This article provides an overview of the nature and causes of distortion and discusses the process and material aspects of distortion specific to steels and tool steels. It also discusses the prediction of distortion and residual stresses by heat treatment simulation for optimizing production processes. The advantages and limitations of heat treatment simulation are also described.