This article discusses the procedures used for pickling nickel and nickel alloys. Nickel alloys can be divided into four groups: high-nickel alloys, nickel-copper alloys, nickel-chromium alloys, and nickel-iron-chromium alloys. Alloys within each composition group that has similar surface conditions are pickled in the same solutions using the same procedures. The article discusses three different surface conditions for pickling these nickel alloys: bright annealed white surface requiring removal of tarnish by flash pickling; bright annealed oxidized surface requiring removal of a layer of reduced oxide, sometimes followed by a flash pickle to brighten; and black or dark-colored surface requiring removal of adherent oxide film or scale. The article also reviews specialized pickling operations of nickel alloys and various cleaning and finishing operations, including grinding, polishing, buffing, brushing, and blasting.

Understanding the high-temperature corrosion behavior of alloys is an important step toward the selection of appropriate alloys for process equipment. This article briefly describes the high-temperature corrosion modes that are frequently encountered in the chemical process industry. These modes include oxidation, carburization, metal dusting, nitridation, halogen corrosion, and sulfidation.

This article describes the effects of furnace atmospheric elements on steels. These elements are air, water vapor, molecular nitrogen, carbon dioxide, and carbon monoxide. The article provides useful information on six groups of commercially important prepared atmospheres classified by the American Gas Association on the basis of method of preparation or on the original constituents employed. These groups are designated and defined as follows: Class 100, exothermic base; Class 200, prepared nitrogen base; Class 300, endothermic base; Class 400, charcoal base; Class 500, exothermic-endothermic base; and Class 600, ammonia base. These are subclassified and numerically designated to indicate variations in the method by which they are prepared. The article also contains a table that lists significant furnace atmospheres and their typical applications.

Passivation; pickling, that is, acid descaling; electropolishing; and mechanical cleaning are important surface treatments for the successful performance of stainless steel used for piping, pressure vessels, tanks, and machined parts in a wide variety of applications. This article provides an overview of the various types of stainless steels and describes the commonly used cleaning methods, namely, alkaline cleaning, emulsion cleaning, solvent cleaning, vapor degreasing, ultrasonic cleaning, and acid cleaning. Finishing operations of stainless steels, such as grinding, polishing, and buffing, are reviewed. The article also explains the procedures of electrocleaning, electropolishing, electroplating, painting, surface blackening, coloring, terne coatings, and thermal spraying. It includes useful information on the surface modification of stainless steels, namely, ion implantation and laser surface processing. Surface hardening techniques, namely, nitriding, carburizing, boriding, and flame hardening, performed to improve the resistance of stainless steel alloys are also reviewed.

This article begins with an overview of steel wire configurations and sizes followed by a discussion on various wiremaking practices. The wiredrawing operation is discussed, including cleaning, die design, use of lubricants and welds, finishes, coating, and thermal treatments. Metallic coatings can be applied to wire by various methods, including hot dip processes, electrolytic process, and metal cladding by rolling metallic strip over the wire. These wires are normally grouped into broad usage categories. These categories, as well as some items in each category, are described in the article under their quality descriptions or commodity names. These include low-carbon steel wire for general usage, wire for structural applications, wire for packaging and container applications, wire for prestressed concrete, wire for electrical or conductor applications, rope wire, mechanical spring wire for general use, wire for fasteners, mechanical spring wire for special applications, upholstery spring construction wire, and alloy wire.

The reflected light microscope is the most commonly used tool to study the microstructure of metals, composites, ceramics, minerals, and polymers. For the study of the microstructure of metals and alloys, light microscopy is employed in the reflected-light mode using either bright-field illumination, dark-field illumination, polarized light illumination, or differential interference contract, generally by the Nomarski technique. This article concentrates on how to reveal microstructure properly to enable the proper identification of the phases and constituents and, if needed, measuring the amount, size, and spacing of constituents, using the light optical microscope. The discussion covers the examination of microstructures using different illumination methods and includes a comparison between light optical images and scanning electron microscopy images of microstructure.

This article provides information on the metallurgy of austenitic stainless steels, and the formation of their intermediate phases (Sigma, Chi, and Laves). It discusses sensitization, a major problem associated with the austenitics, and solutions to avoid the problem. The article describes heat treatments applied to austenitic stainless steels, namely, soaking for homogenization and preparation for hot working; annealing to remove the effects of cold work and to put alloying elements into solid solution; and stress relieving. It provides information on the stabilizing anneal process, which is conducted on stabilized alloys, and discusses the metallurgical characteristics of austenitic stainless steels that may affect the selection of a stress-relieving treatment and prevention of stress corrosion by stress relieving. The article also discusses the heat treatments applied to duplex stainless steels, which involve soaking and annealing, achieving the austenite-ferrite balance, precipitation of intermetallics, and alpha prime precipitation.

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.

This article describes the heat treatment of wrought solid-solution and precipitation-hardening alloys with a focus on the major families of wrought nickel alloys. It also provides information on the heat treatment of some representative solid-solution alloys in the Monel (Ni-Cu), Inconel (Ni-Cr-Mo), Hastelloy (Ni-Mo-Cr), and Incoloy (Ni-Fe-Cr) families of alloys. The heat treatment processes for gamma prime nickel alloys, gamma prime nickel-iron superalloys, and gamma double-prime nickel-iron superalloys are also included. The article also provides information on age-hardenable alloys, and the effects of cold work on aging response and grain growth with examples.

The selection of surface treatments for copper and copper alloys is generally based on application requirements for appearance and corrosion resistance. This article describes cleaning, finishing, and coating processes for copper and copper alloys. These processes include pickling and bright dipping, abrasive blast cleaning, chemical and electrochemical cleaning, mass finishing, polishing and buffing, electroless plating, immersion plating, electroplating, passivation, coloring, and organic coatings.

This datasheet provides information on composition limits, fabrication characteristics, processing effects on physical and mechanical properties, and applications of bright-finishing alloys 5457, 5557, and 5657. A table lists approximate bend radii for 90 deg cold bending of alloy 5557.