Search Results for ferrous metallurgists

This chapter describes some of the technological milestones of the early 20th century, including the invention of tungsten carbide tool steel, the use of age-hardening aluminum in the Wright Flyer , the development of a new heat treating process for aluminum alloys, and Ford’s pioneering use of weight-saving vanadium alloys in Model T cars. It explains how interest in chromium alloys spread throughout the world, spurring the development of commercial stainless steels. The chapter concludes with a bullet point timeline of early 20th century achievements and a brief assessment of more recent innovations.

This appendix is a compilation of terms and definitions related to metallurgy.

This chapter presents the Unified Numbering System (UNS) for metals and alloys.

Ferritic nitrocarburizing accomplishes surface treatment of a part in the ferrite region of the iron-carbon equilibrium diagram. This chapter presents the history and process benefits of ferritic nitrocarburizing.

This chapter discusses the metallurgical considerations and process requirements of nitriding. It presents the pioneering work of Adolph Machlet and Adolph Fry and presents early developments. One such development is the Floe process, a two-stage treatment used to reduce the formation of a compound layer on the surface of a nitrided steel.

This chapter discusses the use of phase diagrams in alloy design, processing, and performance assessment. The examples cover both ferrous and nonferrous metals and a variety of goals and objectives. The chapter also identifies limitations and pitfalls associated with the use of phase diagrams.

This chapter provides an account of the pre-Columbian history of metal discovery in America and then reviews the development of metallurgy in the Middle Ages from early wrought iron practices to the use of coke in iron casting. It discusses the influence of the family of Abraham Darby in England in the development of ironmaking.

This chapter introduces the basic ferrous physical metallurgy principles that need to be understood by the metallographer. The discussion focuses on the variations in microstructures that are generated as a result of the phase transformations that occur during both heat treatment (as in steels) and solidification (as in cast irons). The chapter describes how the development of the iron-carbon phase diagram, coupled with the understanding of the kinetics of phase transformations through the use of isothermal transformation diagram, were breakthroughs in the advancement of ferrous physical metallurgy. Several examples of the morphological features of microstructural constituents in steels are also presented.

This chapter provides a brief history of powder metallurgy from its earliest known uses to present day applications.

This chapter begins with a brief review of the different types of surface treatments and coatings used in industry and their effect on properties and performance. It then discusses the importance of corrosion and wear treatments and the consequences of failing to properly implement them in critical industries such as mining, energy production, transportation, and mineral and chemical processing. The chapter also describes basic approaches to dealing with corrosion and wear in steel.

The formation of martensite is characterized by its athermal transformation kinetics, crystallographic features, and development of fine structure. This chapter describes the diffusionless, shear-type transformation of austenite to martensite and how it affects the morphology and microstructure of heat-treatable carbon steels. It also provides information on lath and plate martensite and how they differ in structure and deformation properties.

Product design requires an understanding of the mechanical properties of materials, much of which is based on tensile testing. This chapter describes how tensile tests are conducted and how to extract useful information from measurement data. It begins with a review of the different types of test equipment used and how they compare in terms of loading force, displacement rate, accuracy, and allowable sample sizes. It then discusses the various ways tensile measurements are plotted and presents examples of each method. It examines a typical load-displacement curve as well as engineering and true stress-strain curves, calling attention to certain points and features and what they reveal about the test sample and, in some cases, the cause of the behavior observed. It explains, for example, why some materials exhibit discontinuous yielding while others do not, and in such cases, how to determine when yielding begins. It also explains how to determine other properties via tensile tests, including ductility, toughness, and modulus of resilience.

Gaseous ferritic nitrocarburizing, like salt bath nitrocarburizing, involves the introduction of carbon and nitrogen into steel in order to produce a thin layer of iron carbonitride and nitrides, the "white layer" or compound layer, with an underlying diffusion zone containing dissolved nitrogen and iron (or alloy) nitrides. This chapter first presents the development and principles of the process. It then discusses the properties of gaseous ferritic nitrocarburized components. The chapter also presents the applications for the ferritic nitrocarburizing process. It provides an overview of the safety considerations.

This chapter explains how metallography and hardness testing are used to evaluate the quality and condition of metal products. It also discusses the use of tensile testing, fracture toughness and impact testing, fatigue testing, and nondestructive test methods including ultrasonic, x-ray, and eddy current testing.

This chapter discusses the characteristics of eutectoid transformations, a type of solid-state transformation associated with invariant reactions, focusing on the iron-carbon system of steel. It describes the compositions, characteristics, and properties of ferrite, eutectoid, hypoeutectoid, and hypereutectoid structures and how they are affected by the addition of various alloying elements. The chapter also discusses the formation of peritectoid structures in the uranium-silicon alloy system.

This appendix provides supplemental information on the metallurgical aspects of atomic structure, the use of dislocation theory, heat treatment processes and procedures, important engineering materials and strengthening mechanisms, and the nature of elastic, plastic, and creep strain components. It also provides information on mechanical property and fatigue testing, the use of hysteresis energy to analyze fatigue, a procedure for inverting equations to solve for dependent variables, and a method for dealing with the statistical nature of failure.

This chapter discusses the development of the nomenclature used to describe the constitution and structure of metals and alloys, particularly the phases observed in the microstructure of steel. It also points out some of the problems with current nomenclature and provides recommendations on how to avoid them.

This chapter concentrates on very low-temperature martensitic transformations, which are of great concern for cryogenic applications and research. The principal transformation characteristics are reviewed and then elaborated. The material classes or alloy systems that exhibit martensitic transformations at very low temperatures are discussed. In particular, the martensitic transformations and their effects in austenitic stainless steels, iron-nickel alloys, practical superconductors, alkali metals, solidified gases, and polymers are discussed.

This chapter describes the two types of Time-Temperature-Transformation (TTT) diagrams used and outlines the methods of determining them. As a precursor to the examination of the decomposition of austenite, it first reviews the phases and microconstituents found in steels. This includes a presentation of the iron-carbon phase diagram and the equilibrium phases. The chapter also covers the common microconstituents that form in steels, including the nomenclature used to describe them. The chapter provides a comparison of isothermal and continuous cooling TTT diagrams. These diagrams are affected by the carbon and alloy content and by the prior austenite grain size, and the way in which these factors affect them is examined.