Search Results for shock-resisting steels

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.

This article discusses the characteristics, composition limits, and classification of wrought tool steels, namely high-speed steels, hot-work steels, cold-work steels, shock-resisting steels, low-alloy special-purpose steels, mold steels, water-hardening steels, powder metallurgy tool steels, and precision-cast tool steels. It describes the effects of surface treatments on the basic properties of tool steels, including hardness, resistance to wear, deformation, and toughness. The article provides information on fabrication characteristics of tool steels, including machinability, grindability, weldability, and hardenability, and presents a short note on machining allowances.

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 describes the six fundamental factors that decide a tool's performance. These are mechanical design, grade of tool steel, machining procedure, heat treatment, grinding, and handling. A deficiency in any one of the factors can lead to a tool and die failure. The article presents a seven-step procedure to be followed when looking for the reason for a failure. A review of the results of the seven-point investigation may lead directly to the source of failure or narrow the field of investigation to permit the use of special tests.

Porcelain enamels are glass coatings applied primarily to products or parts made of sheet steel, cast iron, or aluminum to improve appearance and to protect the metal surface. This article provides information on the types and properties of the porcelain enamels and frits for porcelain enameling. It describes the corrosion resistance of the porcelain enamels in a variety of environments. Evaluation of properties of the porcelain-enameled products to control specifications and quality of porcelain-enamel coatings is also reviewed. The article contains a table that lists the specific test methods for evaluating various properties of porcelain enamels.

This article discusses the materials of construction found in pharmaceutical production facilities. The materials discussed are different stainless steels, nickel and nickel-base alloys, titanium, zirconium, impervious graphite, fluoropolymers, and glass-lined steel. The article describes the three primary causes of failure in the manufacture of pharmaceuticals: embedded iron, failures of glass linings, and corrosion under thermal insulation.

Cemented carbide is, in its simplest form, a metal-matrix composite of tungsten carbide particles in a cobalt matrix. This article describes the microstructure, physical, and mechanical properties of cemented carbides. The properties discussed include thermal conductivity, magnetic properties, corrosion resistance, hardness, fracture toughness, wear resistance, and thermal shock resistance. The article concludes with information on the applications, grade classification, and selection of grades.

Tool steels are carbon, alloy, and high-speed steels that can be hardened and tempered to high hardness and strength values. This article discusses the classifications of commonly used tool steels: water-hardening tool steels, shock-resisting tool steels, cold-work tool steels, and hot-work tool steels. It describes four basic mechanisms of tool steel wear: abrasion, adhesion, corrosion, and contact fatigue wear. The article describes the factors to be considered in the selection of lubrication systems for tool steel applications. It also discusses the surface treatments for tool steels: carburizing, nitriding, ion or plasma nitriding, oxidation, boriding, plating, chemical vapor deposition, and physical vapor deposition. The article describes the properties of high-speed tool steels. It summarizes the important attributes required of dies and the properties of the various materials that make them suitable for particular applications. The article concludes by providing information on abrasive wear and grindability of powder metallurgy steels.

All tool steels are heat treated to develop specific combinations of wear resistance, resistance to deformation or breaking under loads, and resistance to softening at elevated temperature. This article describes recommended heat treating practices, such as normalizing, annealing, austenitizing, quenching, preheating, and tempering commonly employed in certain steels. These are water-hardening tool steels, shock-resisting tool steels, oil-hardening cold-work tool steels, medium-alloy air-hardening cold-work tool steels, high-carbon high-chromium cold-work tool steels, hot-work tool steels, high-speed tool steels, low-alloy special-purpose tool steels, and mold steels. The article presents tables that list the temperature ranges, holding time, and hardness values for all of these heat treating processes.

This article provides an overview of key abradable thermal spray coating systems based on predominant function and key design criteria. It describes two families of coatings which have evolved for use at higher temperature: flame (combustion)-sprayed abradable powders and atmospheric plasma-sprayed abradable powders. Three classic examples of flame spray abradables are nickel-graphite powders, NiCrAl-bentonite powders, and NiCrFeAl-boron nitride powders. The article provides information on various abradable coating testing procedures, namely, abradable incursion testing; aging, corrosion, thermal cycle and thermal shock testing; hardness testing; and erosion resistance testing.

This article discusses the design parameters, operation, characteristics, properties, and advantages of various types of crucible furnaces, such as stationary, tilting, and movable furnaces. It also provides information on the application of the crucible furnaces.

Resistance soldering (RS) can be applied to electrically conductive materials that allow the passage of electric current. The process can be used for selective spot soldering of small components, for the soldering of closely placed parts on an assembly, or for heat restriction when necessary. This article explains that the RS process can be used in all soldering operations and with all solderable metals. It provides information on the applications, preassembly practices, the equipment used and the training required for soldering personnel.

Natural and synthetic rubber linings are used extensively in many industries for their corrosion and/or abrasion resistance. These industries include transportation, chemical processing, water treatment, power, mineral processing, and mining. This article provides information on soft natural rubber, semihard natural rubber, hard natural rubber, neoprene or polychloroprene, chlorobutyl, three-ply linings, nitrile, and ethylene propylene with a diene monomer. Emphasis is placed on advantages, disadvantages, and common uses of each material discussed.

Porcelain enamel is a fusion bonded glass coating that resists chemical and abrasive attack, provides thermal and electrical insulation, and improves aesthetic qualities. It is used on cast iron as well as steel and aluminum alloys. This article provides a review of the porcelain enameling process, the composition of frits, and the preparation of coating substrates. It also provides information on chemical, mechanical, and electrical properties and sheds light on process consistency and quality control.

Ceramics are materials with the potential for a wide range of high-speed finishing operations and for high removal rate machining of difficult-to-machine materials. This article describes the production process, composition, properties, and applications of ceramic tool materials. It presents a comprehensive discussion on the properties and composition of alumina-base tool materials, including alumina and titanium carbide, alumina-zirconia, and silicon carbide whisker reinforced alumina, and silicon nitride base tool materials.

This article describes die wear and failure mechanisms, including thermal fatigue, abrasive wear, and plastic deformation. It summarizes the important attributes required for dies and the properties of the various die materials that make them suitable for particular applications. Recommendations on the selection of the materials for hot forging, hot extrusion, cold heading, and cold extrusion are presented. The article discusses the methods of characterizing abrasive wear and factors affecting abrasive wear. It discusses various die coatings and surface treatments used to extend the lives of dies: alloying surface treatments, micropeening, and electroplating.

Cemented carbides belong to a class of hard, wear-resistant, refractory materials in which the hard carbide particles are bound together, or cemented, by a ductile metal binder. Cermet refers to a composite of a ceramic material with a metallic binder. This article discusses the manufacture, composition, classifications, and physical and mechanical properties of cemented carbides. It describes the application of hard coatings to cemented carbides by physical or chemical vapor deposition (PVD or CVD). Tungsten carbide-cobalt alloys, submicron tungsten carbide-cobalt alloys, and alloys containing tungsten carbide, titanium carbide, and cobalt are used for machining applications. The article also provides an overview of cermets used in machining applications.

Liquid impingement erosion has been defined as progressive loss of original material from a solid surface due to continued exposure to impacts by liquid drops or jets. This article focuses on the core nature of erosion by liquid impingement, due to the greater appreciation of the distinctions between the different forms of erosion. It discusses steam turbine blade erosion, aircraft rain erosion, and rain erosion of wind turbine blades. The article describes the mechanisms of liquid impact erosion and time dependence of erosion rate. It reviews critical empirical observations regarding both impingement variables (velocity, impact angle, droplet size, and physical properties of liquids) and erosion resistance of materials, including the correlation between erosion resistance and mechanical properties and the effects of alloying elements and microstructure. The article also provides information on the ways to combat erosion.