This chapter discusses radiography methods using x-rays, gamma rays, and neutrons. It begins with a discussion on the applications and principles of radiography followed by sections providing information on the sources of radiation, classifications, and characteristics of x-ray tubes. Three primary attenuation processes of electromagnetic radiation, namely photoelectric effect, Compton scattering, and pair production, are covered. The chapter then discusses the principles of shadow formation, the process involved in the conversion of radiation into a form suitable for observation, and the characteristics of x-ray film. It provides information on various exposure factors in film radiography. The chapter provides a description of the characteristics that differentiate neutron radiography from x-ray or gamma ray radiography. The application of neutron radiography is described in terms of its advantages for improved contrast on low atomic number materials, discrimination between isotopes, or inspection of radioactive specimens.

This chapter provides an overview of the various inspection methods used with metals and alloys, namely visual inspection, coordinate measuring machines, machine vision, hardness testing, tensile testing, chemical analysis, metallography, and nondestructive testing. The nondestructive testing methods discussed are liquid penetrant inspection, magnetic particle inspection, eddy current inspection, radiographic inspection, and ultrasonic testing.

The temperature and atmosphere conditions must be precisely controlled in order to achieve the desired metallurgical results during heat treating operations. In order to ensure the repeatability of operation, a heat treating system must have the necessary sensors, timers, and variable (temperature, atmosphere, etc.) controllers to hold the process within prescribed or specified limits. This chapter discusses temperature and atmosphere sensors used in a heat treating system. The temperature sensors covered are contact and noncontact types. The atmosphere sensors covered are oxygen probe, dew point, and infrared. The chapter concludes with an overview of the development of integrated control systems.

Temperature is a critical process parameter in the heat treatment and forging of steel and must be accurately measured to properly control it. This appendix discusses the operating principles of thermocouples and infrared pyrometers, describing the various types as well as advantages and applications.

This appendix explains how to identify crystallographic planes and directions. It shows how Miller indices, a system for specifying crystallographic planes within a unit cell, are determined for cubic and hexagonal systems. It also explains how x-ray diffraction techniques are used in the study of crystalline structures.

This chapter discusses the basic steps of a failure investigation. It explains that the first step is to gather and document information about the failed component and its operating history. It advises investigators to visit the failure site as soon as possible to record damages and collect test specimens for subsequent examination and chemical analysis. It also discusses the role of mechanical property testing, the use of nondestructive evaluation, and the final step of generating a report.

This article introduces procedures an engineer or materials scientist can use to investigate failures. It provides a brief survey of polymer systems and key properties that need to be measured during failure analysis. The article begins with an overview of the problem-solving approach pertinent to structure analysis. This is followed by a review of the characterization of plastics by infrared and nuclear magnetic resonance spectroscopy. The article then provides information on the distribution of molecular weight of an engineering plastic. It further discusses the methods used in thermal analysis, namely differential thermal analysis, thermogravimetric analysis, thermal-mechanical analysis, and dynamic mechanical analysis. The following sections provide details on X-ray diffraction for analyzing crystalline phases and on a minimal scheme for polymer analysis and characterization to assist the design engineer. The article ends with a discussion on the thermal-analytical scheme for analyzing the milligram quantities of polymer samples.

After the fault-tree, a failure-cause identification method has identified potential failure causes and the failure analysis team has prepared a failure mode assessment and assignment (FMA&A). The team knows specifically what to search for when examining components and subassemblies from the failed system. There are numerous techniques and technologies available for examining and analyzing components and subassemblies, which are categorized as follows: optical approaches, dimensional inspection and related approaches, nondestructive test approaches, mechanical and environmental approaches, and chemical and composition analysis for assessing material characteristics. This chapter is a detailed account of the working principle and the steps involved in these techniques and technologies.

This chapter discusses the selection, use, and integration of methods to control process variables in induction heating, including control of workpiece and processing temperature and materials handling systems. The discussion of temperature control includes a review of proportional controllers and heat-regulating devices. Integration of control functions is illustrated with examples related to heating of steel slabs, surface hardening of steel parts, vacuum induction melting for casting operations, and process optimization for electric-demand control. Distributed control within larger manufacturing systems is discussed. The chapter also covers nondestructive techniques for process control and methods for process simulation.

This chapter describes some of the most effective tools for investigating boiler tube failures, including scanning electron microscopy, optical emission spectroscopy, atomic absorption spectroscopy, x-ray fluorescence spectroscopy, x-ray diffraction, and x-ray photoelectron spectroscopy. It explains how the tools work and what they reveal. It also covers the topic of image analysis and its application in the measurement of grain size, phase/volume fraction, delta ferrite and retained austenite, inclusion rating, depth of carburization/decarburization, scale thickness, pearlite banding, microhardness, and hardness profiles. The chapter concludes with a brief discussion on the effect of scaling and deposition and how to measure it.

The physical properties of a material are those properties that can be measured or characterized without the application of force and without changing material identity. This chapter discusses in detail the common physical properties of metals, namely density, electrical properties, thermal properties, magnetic properties, and optical properties. Some physical properties for a number of metals are given in a table.

This chapter discusses the compositions, properties, and applications of nonferrous metals, including zirconium, hafnium, beryllium, lead, tin, gold, silver, and platinum group metals. It also addresses fusible alloys and provides melting temperatures for several compositions.

Beryllium is an extraordinary metal with an unusual combination of physical and mechanical properties. It has low density, high stiffness, and excellent dimensional stability. It is also transparent to x-rays and can be machined to extremely close tolerances. This chapter discusses the properties, compositions, and processing characteristics of beryllium and its alloys. It provides information on powder production and consolidation, commercial designations and grades, wrought products, and forming processes. It also discusses the issue of corrosion, the use of protective treatments and coatings, and health and safety concerns.

Many defects generate excessive heat during operation; this is due to the power dissipation associated with the excess current flow at the defect site. There are several thermal detection techniques for failure analysis and this article focuses on infrared thermography with lock-in detection, which detects an object's temperature from its infrared emission based on blackbody radiation physics. The basic principles and the interpretation of the results are reviewed. Some typical results and a series of examples illustrating the application of this technique are also shown. Brief sections are devoted to the discussion on liquid-crystal imaging and fluorescent microthermal imaging technique for thermal detection.

Electromagnetic induction, or simply "induction," is a method of heating electrically conductive materials such as metals. It is commonly used for heating workpieces prior to metalworking and in heat treating, welding, and melting. This technique also lends itself to various other applications involving packaging and curing of resins and coatings. This chapter provides a brief review of the history of induction heating and discusses its applications and advantages.

The overall chemical composition of metals and alloys is most commonly determined by x-ray fluorescence (XRF) and optical emission spectroscopy (OES). High-temperature combustion and inert gas fusion methods are typically used to analyze dissolved gases (oxygen, nitrogen, and hydrogen) and, in some cases, carbon and sulfur in metals. This chapter discusses the operating principles of XRF, OES, combustion and inert gas fusion analysis, surface analysis, and scanning auger microprobe analysis. The details of equipment set-up used for chemical composition analysis as well as the capabilities of related techniques of these methods are also covered.

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.

To a large extent, the induction coil and its coupling to the workpiece determine the precise heating pattern that is developed. However, it is often desirable to modify this pattern in order to produce a special heating distribution or to increase energy efficiency. At other times, the high heating rates of induction are needed for processing nonconductors. This chapter describes broad methods of accomplishing such objectives: modification of the field of magnetic induction, use of devices to prevent auxiliary equipment or certain portions of a workpiece from being heated, and techniques to apply heating to electrically nonconductive materials. These methods make use of devices such as flux concentrators, shields, and susceptors. The chapter provides a description of the materials for these devices and guidelines for their application.

This appendix provides practical information on induction coils and how they are made. It discusses soldering methods, preferred materials, design challenges, and best practices and procedures. It also discusses the design, construction, and application of magnetic flux concentrators and the growing use of computer simulation.