Fabrication of wrought stainless steels requires use of greater power, more frequent repair or replacement of processing equipment, and application of procedures to minimize or correct surface contamination because of its greater strength, hardness, ductility, work hardenability and corrosion resistance. This article provides a detailed account of such difficulties encountered in the fabrication of wrought stainless steel by forming, forging, cold working, machining, heat treating, and joining processes. Stainless steels are subjected to various heat treatments such as annealing, hardening, and stress relieving. Stainless steels are commonly joined by welding, brazing, and soldering. The article lists the procedures and precautions that should be instituted during welding to ensure optimum corrosion resistance and mechanical properties in the completed assembly.

Precipitation hardening is a hardening mechanism found in various steels and alloy systems, such as nickel-, cobalt-, titanium-, copper-, and iron-base alloys. This article provides a brief description of precipitation hardening process, furnace equipment, surface-related problems, and protective atmospheres used in heat treatment of iron-base precipitation-hardenable (PH) superalloys. It focuses on various factors to be considered in heat treating of PH stainless steels: cleaning prior to heat treatment, furnace atmospheres, time-temperature cycles, variations in cycles, and scale removal after heat treatment. The article describes the mechanical properties, solution treatment, and aging treatment for many martensitic PH alloys, including: Alloy 17-4 PH, Alloy 13-8 Mo, Alloy 15-5 PH, Custom 450, and Custom 455; as well as semiaustenitic PH stainless steels such as Alloy 17-7 PH, Alloy PH 15-7 Mo, AM-350, Pyromet 350, AM-355, and Pyromet 355; austenitic PH stainless steel, A-286; cast PH stainless steels; and iron-nickel PH superalloys.

This article summarizes the key mechanical characteristics of various types of stainless steel, including ferritic, austenitic, martensitic, precipitation hardening, and duplex steels. Particular emphasis is on fracture properties and corrosion fatigue. The article tabulates typical room-temperature mechanical properties and fatigue endurance limits of stainless steels. Stainless steels are susceptible to embrittlement during thermal treatment or elevated-temperature service. The article discusses embrittlement in terms of sensitization, 475 deg C embrittlement, and sigma-phase embrittlement. It also describes the effect of environment on fatigue crack growth rate.

This article describes metallographic preparation and examination techniques for stainless steels and maraging steels. It presents a series of micrographs demonstrating microstructural features of these alloys. Procedures used to prepare stainless steels for macroscopic and microscopic examination are similar to those used for carbon, alloy, and tool steels. Cutting and grinding must be carefully executed to minimize deformation because the austenitic grades work harden readily. The high-hardness martensitic grades that contain substantial undissolved chromium carbide are difficult to polish while fully retaining the carbides. Unlike carbon, alloy, and tool steels, etching techniques are more difficult due to the high corrosion resistance of stainless steels and the various second phases that may be encountered. The microstructures of stainless steels can be quite complex. Matrix structures vary according to the type of steel, such as ferritic, austenitic, martensitic, precipitation hardenable, or duplex.

Low-temperature surface hardening is mostly applied to austenitic stainless steels when a combination of excellent corrosion performance and wear performance is required. This article provides a brief history of low-temperature surface hardening of stainless steel, followed by a discussion on physical metallurgy, including crystallographic identity, thermal stability and decomposition, nitrogen and carbon solubility in expanded austenite, and diffusion kinetics of interstitials. It provides a description of low-temperature nitriding and nitrocarburizing processes for primarily austenitic and, to a lesser extent, other types of stainless steels along with practical examples and industrial applications of these steels.

Martensitic stainless steels are the least corrosion-resistant of all stainless alloys. The traditional martensitic stainless steels are iron/chromium/carbon alloys, sometimes with a small amount of nickel and/or molybdenum. This article provides an overview on the influences of the various possible alloying elements on the key properties of martensitic stainless steels. It describes the various preparation processes, namely, atmosphere selection, cleaning, and preheating, prior to heat treatment for these steels. Common heat treatment methods include annealing, hardening, tempering, and stress relieving. The article lists the compositions of casting alloys and also describes the effect of tempering temperature on the hardness, strength, ductility, and toughness properties of the alloys.

Repair and maintenance of parts and components is carried out as a logical procedure that ensures the production of a usable and safe component or it can be approached haphazardly. This article describes the requirements and repair techniques of arc and oxyfuel welding processes to repair weld defects and structural failures. It further discusses the preliminary assessment and base-metal preparation involved in weld repair. Furthermore, the article provides information on the general repair guidelines that are followed to ensure successful weld repairs of both ferrous (carbon steels, cast irons, and stainless steels) and nonferrous (titanium) base metals.

Stainless steels are widely used at elevated temperatures when carbon and low-alloy steels do not provide adequate corrosion resistance and/or sufficient strength at these temperatures. This article deals with the wrought stainless steels used for high temperature applications. It gives some typical compositions of wrought heat-resistant stainless steels, which are grouped into ferritic, martensitic, austenitic, and precipitation-hardening (PH) grades. Quenched and tempered martensitic stainless steels are essentially martensitic and harden when air cooled from the austenitizing temperature. These alloys offer good combinations of mechanical properties. The article focuses on mechanical property considerations and corrosion resistance considerations of stainless steels. The corrosion and oxidation resistance of wrought stainless steels is similar to that of cast stainless steels with comparable compositions.

This article commences with a brief description of the solidification characteristics and microstructures of martensitic precipitation hardening (PH) stainless steels. It reviews the welding parameters for types 17-4PH, 15-5PH, PH13-8 Mo, Custom 450, and Custom 455. The article describes the microstructural evolution and weld parameters associated with semiaustenitic PH steels. It discusses the weldability and welding recommendations for A-286 and JBK-75 austenitic PH stainless steels. The article also presents tables that list properties and heat treatments for the PH stainless steels.

Stainless steels are used for medical implants and surgical tools due to the excellent combination of properties, such as cost, strength, corrosion resistance, and ease of cleaning. This article describes the classifications of stainless steels, such as austenitic stainless steels, martensitic stainless steels, ferritic stainless steels, precipitation-hardening stainless steels, and duplex stainless steels. It contains a table that lists common medical device applications for stainless steels. The article discusses the physical metallurgy and physical and mechanical properties of stainless steels. Medical device considerations for stainless steels, such as fatigue strength, corrosion resistance, and passivation techniques, are reviewed. The article explains the process features of implant-grade stainless steels, including type 316L, type 316LVM, nitrogen-strengthened, ASTM F1314, ASTM F1586, ASTM F2229, and ASTM F2581 stainless steels.

The warm and hot working of metals provide the ability to shape important materials into component shapes that are useful in a variety of applications requiring strength, toughness, and ductility. This article focuses on a variety of metals that can be hot or warm worked, and describes the characteristics and processing considerations of each metal. It discusses forging because it is a versatile metalworking process and performed at cold, warm, and hot working temperatures. The article also presents the applications of steels, stainless steels, aluminum alloys, titanium alloys, superalloys, and copper alloys.

This article discusses the composition, characteristics, and properties of the five groups of wrought stainless steels: martensitic stainless steels, ferritic stainless steels, austenitic stainless steels, duplex stainless steels, and precipitation-hardening stainless steels. The selection of stainless steels may be based on corrosion resistance, fabrication characteristics, availability, mechanical properties in specific temperature ranges and product cost. The fabrication characteristics of stainless steels include formability, forgeability, machinability, and weldability. The product forms of wrought stainless steels are plate, sheet, strip, foil, bar, wire, semifinished products, pipes, tubes, and tubing. The article describes tensile properties, elevated-temperature properties, subzero-temperature properties, physical properties, corrosion properties, and fatigue strength of stainless steels. It characterizes the experience of a few industrial sectors according to the corrosion problems most frequently encountered and suggests appropriate grade selections. Corrosion testing, surface finishing, mill finishes, and interim surface protection of stainless steels are also discussed.

Low-temperature carburization hardens the surface of austenitic stainless steels through the diffusion of interstitial carbon without the formation of carbides. This article provides an overview on austenitic stainless steels and low-temperature carburization. It reviews the competing technologies and commercial application of low-temperature carburization. The article discusses several processing parameters, including activation of the surface, proper surface preparation, selection and condition of the alloy to be carburized, treatment temperature, and carburizing atmosphere for successful low-temperature carburization of austenitic stainless steels and other chromium-containing alloys. It describes the performance properties of the low-temperature carburized layer: fatigue resistance, wear resistance, erosion resistance, and corrosion resistance.

Stainless steels are primarily alloys of iron and chromium. They are grouped into five families, primarily based on their microstructure: ferritic, austenitic, martensitic, duplex, and precipitation hardening. Three out of the five families of stainless steels, namely, austenitic, ferritic, and martensitic, are well suited for manufacture via conventional powder metallurgy (PM) processes. This article presents the iron-chromium partial phase diagram to illustrate the changes in the temperature range when pure iron is alloyed with chromium. It describes AISI and UNS numbering systems, which are used as an identification system for stainless steels. The article tabulates the material designations of stainless steels in accordance with the Metal Powder Industries Federation. It also details the characteristics and chemical composition of wrought and PM stainless steels.

Heat treating of stainless steel produces changes in physical condition, mechanical properties, and residual stress level and restores maximum corrosion resistance when that property has been adversely affected by previous fabrication or heating. This article focuses on annealing of different types of stainless steels such as austenitic, ferritic, duplex, martensitic, and precipitation-hardening, and on the heat treatment of superalloys and refractory metals. It discusses the recommended procedures for solution annealing, austenite conditioning, transformation cooling, and age tempering of precipitation-hardening stainless steels. The article also lists general recommendations for the annealing temperatures of tantalum, niobium, molybdenum, tungsten, and their alloys.

Stainless steels are iron-base alloys containing minimum of approximately 11% Cr, and owing to its excellent corrosion resistance, are used for wide range of applications. These applications include nuclear reactor vessels, heat exchangers, oil industry tubular, chemical processing components, pulp and paper industries, furnace parts, and boilers used in fossil fuel electric power plants. The article provides a brief introduction on corrosion resistance of wrought stainless steel and its designations. It lists the chemical composition and describes the physical and mechanical properties of five major stainless steel families, of which four are based on the crystallographic structure of the alloys, including martensitic, ferritic, austenitic, or duplex. The fifth is precipitation-hardenable alloys, based on the type of heat treatment used. The article further discusses the factors in the selection of stainless steel, namely corrosion resistance, fabrication characteristics, product forms, thermally induced embrittlement, mechanical properties in specific temperature ranges, and product cost.

The machinability of stainless steels varies from low to very high, depending on the final choice of the alloy. This article discusses general material and machining characteristics of stainless steel. It briefly describes the classes of stainless steel, such as ferritic, martensitic, austenitic, duplex, and precipitation-hardenable alloys. The article examines the role of additives, such as sulfur, selenium, tellurium, lead, bismuth, and certain oxides, in improving machining performance. It provides ways to minimize difficulties involved in the traditional machining of stainless steels. The article describes turning, drilling, tapping, milling, broaching, reaming, and grinding operations on stainless steel. It concludes with information on some of the nontraditional machining techniques, including abrasive jet machining, abrasive waterjet machining electrochemical machining, electron beam machining, and plasma arc machining.

Characteristics of stainless steel that affect its formability include yield strength, tensile strength, and ductility, in addition to the effect of work hardening on these properties. This article discusses the forming process of stainless steel, heat-resistant alloys and refractory metals, detailing the major aspects of forming, including formability, lubrication, and forming methods and tools. The effect of factors such as alloy condition, cold reduction, forming direction (in the case of heat-resistant alloys) and temperature (in the case of refractory metals) on formability is also discussed.