This article covers the three most popular techniques used to characterize the very outermost layers of solid surfaces: Auger electron spectroscopy (AES), X-ray photoelectron spectroscopy (XPS), and time-of-flight secondary ion mass spectrometry (TOF-SIMS). Some of the more important attributes are listed for preliminary insight into the strengths and limitations of these techniques for chemical characterization of surfaces. The article describes the basic theory behind each of the different techniques, the types of data produced from each, and some typical applications. Also discussed are the different types of samples that can be analyzed and the special sample-handling procedures that must be implemented when preparing to do failure analysis using these surface-sensitive techniques. Data obtained from different material defects are presented for each of the techniques. The examples presented highlight the typical data sets and strengths of each technique.

This article provides a detailed account of the basic concepts of Rutherford backscattering spectrometry (RBS). It begins with a description of the principles of RBS, as well as the effect of channeling in conjunction with backscattering measurements and the effect of energy loss under this condition. This is followed by a section on equipment used in RBS analysis. Channel-energy conversion, energy-depth conversion, and separation of the dechanneling background are then discussed as the main steps of RBS data analysis. The article also discusses the applications of RBS—including composition of bulk samples, thin-film composition and layer thickness, impurity profiles, damage depth profile, and surface peak—as well as the various codes developed to simulate it.

X-ray topography is the general term for a family of x-ray diffraction imaging techniques capable of providing information on the nature and distribution of imperfections. This article provides a detailed account of x-ray topography techniques, providing information on the historical background and development trends in x-ray diffraction topography. The discussion covers the general principles, components of systems, and applications of x-ray topography techniques, namely conventional X-ray topographic techniques and synchrotron x-ray topographic techniques.

This article is an overview of the division Surface Analysis of this volume. The division covers various developed surface-analysis techniques, such as scanning probe and atomic force microscopy. The division focuses on the analysis of surface layers that are less than 100 nm. A quick reference summary of surface-analysis methods is presented in this article.

This article discusses the basic principles of and chemical effects in Auger electron spectroscopy (AES), covering various factors affecting the quantitative analyses of AES. The discussion covers instrumentation and sophisticated electronics typically used in AES for data acquisition and manipulation and various limitations of AES. Various examples highlighting the capabilities of the technique are also included.

This article provides an overview of scanning probe microscopes (scanning tunneling microscope and atomic force microscope (AFM)), covering the various operating modes and probes used in these instruments and providing information on AFM instrumentation, applications, and analyses.

This article focuses on the principles and applications of X-ray photoelectron spectroscopy (XPS) for the analysis of elemental and chemical composition. The discussion covers the nomenclature, instruments, and specimen preparation process of XPS. Some of the factors pertinent to the calibration of materials for accurate measurements using XPS are provided, along with some aspects of the accuracy in quantitative analysis by XPS. In addition, the article presents examples of how XPS data can be used to solve problems with surface interactions.

This article focuses on the principles and applications of thermal desorption spectroscopy (TDS) use to study adsorption, desorption, and reaction of adsorbed atoms and molecules on surfaces. The discussion provides information on various components of and specimen preparation processes for a TDS experiment. The factors that must be considered when performing TPD experiments and several methods of analyzing TPD data are covered. A few studies where TPD was used to elucidate surface reactions that impact the tribological performances of materials are also discussed.

This article focuses on nondestructive inspection of steel bars. The primary objective in the nondestructive inspection of steel bars and wire is to detect conditions in the material that may be detrimental to the satisfactory end use of the product. The article discusses various types of flaws encountered in the inspection of steel bars, including porosity, inclusions, scabs, cracks, seams, and laps. Inspection methods, such as magnetic-particle inspection. liquid penetrant inspection, ultrasonic inspection, and electromagnetic inspection, of steel bars are also described. The article provides a discussion on electromagnetic systems, eddy-current systems, and magnetic permeability systems for detection of flaws on steel bars. It concludes with a description of nondestructive inspection of steel billets.

This article introduces the principal methodologies and some advanced technologies that are being applied for nondestructive evaluation (NDE) of fiber-reinforced polymer-matrix composites. These include acoustic emission, ultrasonic, eddy-current, computed tomography, electromagnetic acoustic transducer, radiography, thermography, and low-frequency vibration methods. The article also provides information on NDE methods commonly used for metal-matrix composites.

This article provides information on the application of nondestructive examination (NDE) technologies to tube and pipe products. These include modeling and simulation methods, eddy-current methods, magnetic methods, acoustic methods, and physical methods. A summary of nondestructive examination methods based on flaw type and product stage is presented in a table. The article also discusses in-service inspection of tubular products and presents an example that illustrates the importance of nondestructive testing (NDT) for welds in austenitic stainless steel tubing.

A number of nondestructive evaluation (NDE) methods, such as radiography, ultrasound, and eddy current, are available to detect flaws in solid materials. This article describes the fundamental aspects of these NDE methods in terms of operation principles. It presents some examples of the methods performed on various types of flaws resulting from solid-state welding processes.

The success of a reliable non-destructive evaluation (NDE) application depends greatly on the expertise and thoroughness of the NDE engineering that is performed. This article discusses the general considerations of NDE in terms of NDE response and NDE system management and schedule. It describes the NDE engineering and NDE process control, along with some case studies related to the applications of NDE. The article reviews various models for predicting NDE reliability, such as ultrasonic inspection model, eddy current inspection model, and radiographic inspection model. It concludes with an example that illustrates the integration of an ultrasonic reliability model with a CAD system.

Additive manufacturing (AM) is the process of joining materials to make parts from three-dimensional (3D) model data, usually layer upon layer, as opposed to subtractive manufacturing and formative manufacturing methodologies. This article discusses various defects in AM components, such as porosity, inclusions, cracking, and residual stress, that can be avoided by using vendor recommended process parameters and approved materials. It describes the development of process-structure-property-performance modeling. The article explains the practical considerations in nondestructive evaluation for additively manufactured metallic parts. It also examines nondestructive testing (NDT) inspection and characterization methods for each of the manufacturing stages in their natural order. The article provides information on various inspection techniques for completed AM manufactured parts. The various electromagnetic and eddy current techniques that can be used to detect changes to nearsurface geometric anomalies or other defects are also discussed. These include ultrasonic techniques, radiographic techniques, and neutron imaging.

Eddy-current inspection is based on the principles of electromagnetic induction and is used to identify or differentiate among a wide variety of physical, structural, and metallurgical conditions in electrically conductive ferromagnetic and nonferromagnetic metals and metal parts. This article discusses the advantages and limitations of eddy-current inspection, as well as the development of the eddy-current inspection process. It reviews the principal operating variables encountered in eddy-current inspection: coil impedance, electrical conductivity, magnetic permeability, lift-off and fill factors, edge effect, and skin effect. The article illustrates some of the principal impedance concepts that are fundamental to understanding of and effective application of eddy-current inspection. It discusses various types of eddy-current instruments, such as the resistor and single-coil system, bridge unbalance system, induction bridge system, and through transmission system. The article concludes with a discussion on the inspection of aircraft structural and engine components.

The potential for introducing defects during processing becomes greater as the relative density of pressed and sintered powder metallurgy (PM) parts increases and more multilevel parts with complex geometric shapes are produced. This article discusses the potential defects in pressed and sintered PM parts: density variations, compaction and ejection cracks, microlaminations, poor degree of sintering, and voids from prior lubricant agglomerates. It describes the various methods applicable to green compacts: direct-current resistivity testing, radiographic techniques, computed tomography, and gamma-ray density determination. The article also discusses the methods for automated nondestructive testing of pressed and sintered PM parts: acoustic methods-resonance testing, eddy current testing, magnetic bridge comparator testing, ultrasonic techniques, radiographic techniques, gamma-ray density determination, and visual inspection.

Nondestructive inspection (NDI) methods for cast iron are used to ensure that the parts supplied perform as required by the purchaser. This article focuses on the principal nondestructive methods used to inspect for anomalies in cast irons and to determine if the volume, shape, size, or number of these anomalies exceeds the maximum allowed by the purchaser. The nondestructive methods include visual inspection, dimensional inspection, liquid penetrant inspection, magnetic-particle inspection, eddy-current inspection, radiographic inspection, ultrasonic inspection, resonant testing, and leak testing. The technique, strengths, and weaknesses of each of the nondestructive methods are also discussed.

Heat treatment of aluminum alloys is assessed by various quality-assurance methods that include metallographic examination, hardness measurements, mechanical property tests, corrosion-resistance tests, and electrical conductivity testing. The use of hardness measurements in the quality assurance of heat treated aluminum products is effectively used in conjunction with the measurement of surface electrical conductivity. This article provides a detailed discussion of the error sources in eddy-current conductivity measurements. It also presents useful information on the variation of electrical conductivity of alloy 2024 samples as a function of aging time at different isothermal holding temperatures.