This chapter discusses the techniques applicable to the diagnosis of corrosion failures, including visual and microscopic examination of corroded surfaces and microstructure; chemical analysis of the metal, corrosion products, and bulk environment; nondestructive evaluation methods; corrosion testing techniques; and mechanical testing techniques. A guide to investigative techniques used in corrosion failure analysis is provided in a table, describing the advantages and limitations of each technique. The principal stages of the investigation and analysis of corrosion failures discussed in the chapter are: collection of background information and sampling; preliminary laboratory examination; detailed metallographic and fractographic examinations; chemical analysis of corrosion products and bulk materials; corrosion testing for quality control; mechanical testing for quality control; and analysis of results and report writing.

This article discusses the chemical susceptibility of a polymeric material. The discussion covers significant absorption and transportation of an environmental reagent by the polymer; the chemical susceptibility of additives; and thermal degradation, thermal oxidative degradation, photo-oxidative degradation, environmental corrosion, and chemical corrosion of polymers. It also includes some of the techniques used to detect changes in structure during polymer exposure to hostile environments. In addition, the article describes the effects of environment on polymer performance, namely plasticization, solvation, swelling, environmental stress cracking, polymer degradation, surface embrittlement, and temperature effects.

This appendix is a comprehensive collection of selected sources related to corrosion properties of materials and corrosion testing.

This article reviews various analytical techniques most commonly used in plastic component failure analysis. The description of the techniques is intended to make the reader familiar with the general principles and benefits of the methodologies. The descriptions of the analytical techniques are supplemented by a series of case studies that include pertinent visual examination results and the corresponding images that aided in the characterization of the failures. The techniques covered include Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, thermomechanical analysis, and dynamic mechanical analysis. The article also discusses various analytical methods used to characterize the molecular weight distribution of a polymeric material. It provides information on a wide range of mechanical tests that are available to evaluate plastics and polymers, covering the various considerations in the selection and use of test methods.

Superalloys are susceptible to damage from a variety of surface contaminants. They may also require special surface finishes for subsequent processing steps such as coating applications. This chapter describes some of the cleaning and finishing procedures that have been developed for superalloys and how they work. It discusses the effect of metallic contaminants, tarnish, oxide, and scale and how they can be detected and removed. It also discusses chemical and mechanical surface finishing techniques and where they are used, and presents several application examples.

This chapters discusses the basic steps in the failure analysis process. It covers examination procedures, selection and preservation of fracture surfaces, macro and microfractography, metallographic analysis, mechanical testing, chemical analysis, and simulated service testing.

This article focuses on characterization techniques used for analyzing the physical behavior and chemical composition of thermoset resins, namely chromatography and infrared spectroscopy. The main purpose is to give sufficient detail to permit the reader understand a particular test technique and its value to the thermoset resin field. Epoxy resins are emphasized in the examples because they dominate the airframe and aerospace industries. The article also provides information on two categories of characterization of the processing behavior of thermoset. The first studies the thermal properties of reactive thermoset systems, while the second utilizes these thermal characteristics as the basis for monitoring and control during processing.

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 chapter discusses the role of standards and specifications for steel castings. It defines specifications and discusses how certification, testing, examination, methods, practices, procedures, compositions, properties, facilities, statistical process control, and documentation relate to codes and standards. The chapter describes processes involved in the selection of specifications for steel castings. Further, it provides information on the cost of specifications.

The testing of plastics includes a wide variety of chemical, thermal, and mechanical tests. This chapter reviews the tensile testing of plastics, which has been standardized in ASTM D 638, "Standard Test Method for Tensile Properties of Plastics," and other comparable standards. It describes the fundamental factors that affect data from tensile tests, examines the stipulations in standardized tensile testing, and discusses the utilization of data from tensile tests.

This chapter covers the fatigue and fracture behaviors of ceramics and polymers. It discusses the benefits of transformation toughening, the use of ceramic-matrix composites, fracture mechanisms, and the relationship between fatigue and subcritical crack growth. In regard to polymers, it covers general characteristics, viscoelastic properties, and static strength. It also discusses fatigue life, impact strength, fracture toughness, and stress-rupture behaviors as well as environmental effects such as plasticization, solvation, swelling, stress cracking, degradation, and surface embrittlement.

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.

This chapter concerns itself with the tribology of ceramics, cermets, and cemented carbides. It begins by describing the composition and friction and wear behaviors of aluminum oxide, silicon carbide, silicon nitride, and zirconia. It then compares and contrasts the microstructure, properties, and relative merits of cermets with those of cemented carbides.

The crux of this chapter is to develop a method to quantitatively define hardenability. The chapter includes the empirical methods to estimate the hardenability knowing the chemical composition, describes prior austenite grain size, and examines their utility. It then reviews the Jominy end-quench test and explains its relation to hardenability. The chapter outlines the concepts of the critical diameter and the ideal critical diameter, leading to establishing a quantitative measure of hardenability. Next, it examines methods that have been developed which allow estimation of the ideal critical diameter from the chemical composition and the austenite grain size. The chapter reviews the methods which allow calculation of the Jominy curve from a value of the ideal critical diameter. Additionally, it describes the selection and application of H-band steels. Finally, the chapter describes the effect of boron on the hardenability of steels.

This chapter provides an overview of the possible mechanisms of failure for heat treated steel components and discusses the techniques for examining fractures, ductile and brittle failures, intergranular failure mechanisms, and fatigue. It begins with a description of the general sources of component failure. This is followed by a section on the stages of a failure analysis, which can proceed one after the other or occur at the same time. These stages of analysis are collection of background data, preliminary visual examination, nondestructive testing, selection and preservation of specimens, mechanical testing, macroexamination, microexamination, metallographic examination, determination of the fracture mechanism, chemical analysis, exemplar testing, and analysis and writing the report. The chapter ends with a discussion on various processes involved in the determination of the fracture mechanism.

This chapter discusses field, visual, physical, and metallurgical examinations of gear failures. Physical examinations reviewed include nondestructive testing, including magnetic-particle inspection, tooth characteristic studies, surface hardness testing, ultrasonic testing, nital etching, profilometer measurements, and dimensional checking. Metallurgical examinations reviewed include the cross-sectional hardness survey, macroscopic examination, carbon gradient traverse, chemical analysis, case hardness traverse [microhardness], microscopic examination, and scanning electron microscopy.

This chapter discusses the types of failures that can occur in sheet metal forming tools and explains how to mitigate their effects. It describes the factors that influence galling and wear and the benefits of special treatments and coatings. It provides information on through hardening, case (surface) hardening, and nitriding as well as hard chrome plating, vapor deposition, and thermal diffusion coating. It explains how to measure wear resistance using various tests and provides guidelines for selecting tool materials, treatments, and coatings.

Adhesive bonding is a widely used industrial joining process in which a polymeric material is used to join two separate pieces (the adherends or substrates). This chapter begins with a discussion on the advantages and disadvantages of adhesive bonding, followed by a section providing information on the theory of adhesion. The chapter then describes the considerations for designing adhesively bonded joints and for testing or characterizing adhesive materials. The following section covers the characteristics of the most important synthetic adhesive systems and five groups of adhesives, namely structural, hot melt, pressure sensitive, water based, and ultraviolet and electron beam cured. The chapter ends with a discussion on some general guidelines for adhesive bonding and the basic steps in the adhesive bonding process.

A driven gear in the gear box of an aircraft engine fractured after a 40 h test run. The driving gear and gear shaft were also damaged. Based on the results of fractography, chemical analysis, metallography, and hardness testing, the fracture was caused by a fatigue crack initiating at the corner of the inner rim near an inclusion. The report recommends the use of a cleaner material and more carefully controlling case hardening process.

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