This article provides an overview of austenitic manganese steels. It describes the standard composition ranges of commercial products and explains how various alloying elements affect mechanical properties, processing, and performance. The article also discusses special grades of manganese steels and the types of applications for which they have been developed.

Alloy steels are alloys of iron with the addition of carbon and one or more of the following elements: manganese, chromium, nickel, molybdenum, niobium, titanium, tungsten, cobalt, copper, vanadium, silicon, aluminum, and boron. Alloy steels exhibit superior mechanical properties compared to plain carbonsteels as a result of alloying additions. This chapter describes the beneficial effects of these alloying elements in steels. It discusses the mechanical properties, nominal compositions, advantages, and engineering applications of various classes of alloy steels. They are low-alloy structural steels, SAE/AISI alloy steels, high-fracture-toughness steels, maraging steels, austenitic manganese steels, high-strength low-alloy steels, dual-phase steels, and transformation-induced plasticity steels.

This chapter describes the processes involved in heat treatment of carbon and low alloy steel, high strength low alloy steels, austenitic manganese steels, martensitic stainless steels, and austenitic stainless steels. In addition, precipitation hardening and quench hardening of carbon steel is also covered.

This chapter covers the basics of weldability of cast steels such as carbon and low alloy steels, corrosion-resistant high alloy steels, nickel-base alloys, heat-resistant high alloy steels, and wear-resistant high austenitic manganese steels. It provides an overview of weld overlay and hard facing; cast-weld construction; and plasma arc cutting and plasma arc welding. The chapter discusses different types of welding processes. These include shielded metal-arc welding, air carbon arc cutting process, gas tungsten-arc welding, gas metal-arc welding process, flux-cored arc welding, submerged arc welding, and electroslag and electro-gas welding.

This chapter describes the physical properties of steels used for castings. The properties covered include density, modulus of elasticity, Poisson's ratio, shear modulus, thermal expansion, thermal conductivity, specific heat, thermal diffusivity, electrical resistivity, and magnetic properties.

This chapter provides the definitions of fundamental wear mechanisms. The chapter describes the properties and applications of materials used for wear resistance. It discusses the processes involved in screening tests for wear resistance. In addition, the practical application of wear-resistant principles is covered.

This chapter introduces the metallographer to the various types of steels and cast irons and explains how they are classified and defined. Classification and designation details are provided for plain carbon steels, alloy steels, and gray, white, ductile, and malleable cast irons.

Steel is broadly classified as plain-carbon steels, low-alloy steels, and high-alloy steels. This chapter begins by describing microconstituents of low- and medium-carbon steel, including bainite and martensite. This is followed by a section discussing the effect of alloying elements on steel. Then, it provides an overview of steel casting applications. Next, the chapter reviews engineering guidelines for steel castings and feeder design. The following section provides information on feeding aids. Further, the chapter describes the elements of gating systems for steel castings. It also describes the alloys, properties, applications, and engineering details of steel. Finally, the chapter explains defects in steel castings and presents guidelines for problem solving with examples.

This chapter describes the classification of steels and the various compositional categories of commercial steel products. It explains how different alloying elements affect the properties of carbon and low-alloys steels and discusses strength, toughness, and corrosion resistance and how to improve them.

This chapter defines steel castings, explains when to use steel castings, gives an overview of casting processes, and gives examples of suitable applications for cast steel parts.

With cold work, mechanical strength (measured either by yield strength or ultimate tensile strength) increases and ductility (measured by elongation, reduction of area, or fracture toughness) normally decreases. This chapter discusses the mechanisms that produce these changes and the factors that influence them. It explains how cold working increases dislocation density and how that affects the stress-strain characteristics of steel, particularly the onset of deformation. It describes the effects of deformation on ferrite, austenite, cementite, and pearlite, and how to optimize their microstructure for various applications through controlled deformation. It also provides information on subcritical annealing, the examination and control of texture, the use of optical microscopy to monitor the effects of recrystallization, and the effect of cold working on threaded fasteners, nails, and filaments used to manufacture cords.

This article discusses the role of alloying in the production and use of carbon and low-alloy steels. It explains how steels are defined and selected based on alloy content and provides composition and property data for a wide range of designations and grades. It describes the effect of alloying on structure and composition and explains how alloy content can be controlled to optimize properties and behaviors such as ductility, strength, toughness, fatigue and fracture resistance, and resistance to corrosion, wear, and high-temperature creep. It also examines the effect of alloying on processing characteristics such as hardenability, formability, weldability, machinability, and temper embrittlement. In addition, the article provides an extensive amount of engineering data with relevance in materials selection.

Steel castings are produced in thousands of designs for different applications. They fill needs in many industries, including transportation, construction machinery, earthmoving equipment, rolling mills, mining, oil and gas exploration, and power generation. This chapter touches upon the variety of applications for which steel castings can be supplied and the ranges of casting size and complexity. Photographs in this chapter provide an understanding of these applications, their size and complexity, and the types of cast steels produced.

This chapter presents the factors affecting machinability. It provides a detailed discussion on the machining of steel castings. These include microstructure effects, hardness and strength effects, turning, face milling and drilling, casting surface effects, and weld area effects. The chapter also presents an overview of machining practices.

This chapter covers a broad range of low-carbon steels optimized for structural applications. Low-carbon structural steels are generally considered the highest-strength steels that can be welded without undue difficulty, even in the field. They include mild steels, carbon-manganese and niobium- and vanadium-containing steels, and high-strength low-alloy steels. Chapter 5 discusses the composition, microstructure, and properties of these workhorse materials and explains how to identify the cause of production-related issues such as lamellar tearing and ferrite-pearlite banding. It also describes some of the alloying variations that have been developed to improve machinability and the mechanisms by which they work.

Microstructures can be altered intentionally or unintentionally. In some cases, metallographers must diagnose what may have happened to the steel or cast iron based on the microstructural details. This chapter discusses how microstructure in steels and cast irons can be intentionally altered during heat treatment, solidification, and deformation (hot and cold working). Some specific examples are then shown to illustrate what can go wrong through unintentional changes in microstructure, for example, the loss of carbon from the surface of the steel by the process known as decarburization or the buildup of brittle carbides on the grain boundaries of an austenitic stainless steel by the process known as sensitization.

This chapter briefly discusses the characteristics of mechanical twins and stacking faults in close-packed planes. It provides an overview of the composition, microstructures, thermodynamics, processing, deformation mechanism, mechanical properties, formability, and special attributes of twinning-induced plasticity steels.

Steels contain a wide range of elements, including alloys as well as residual processing impurities. This chapter describes the chemical composition of low-alloy AISI steels, which are classified based on the amounts of chromium, molybdenum, and nickel they contain. It explains why manganese is sometimes added to steel and how unintended consequences, such as the development of sulfide stringers, can offset the benefits. It also examines the effect of alloying elements on the iron-carbon phase diagram, particularly their effect on transformation temperatures.