Industrial computed tomography data analysis is harnessing deep learning to both accelerate in-line inspection and build better products. This article includes a case history involving deep learning industrial CT scan data analysis.

This article summarizes the more common analytical techniques for studying ancient metal artifacts, illustrated by case histories. There are two main classifications: noninvasive and invasive techniques. This distinction is of prime importance because some heritage objects may be too rare or valuable for invasive sampling, or there may be ethical objections to certain types of examination. Noninvasive examination of ancient metal artifacts is important, yet it cannot provide the detailed information obtainable from invasive techniques. This is especially true when artifacts contain “hidden” damage and there is also a need for accurate quantitative analyses.

Although stress corrosion cracking (SCC) accounts for just a fraction of all engineering failures, its prevention is a major problem, particularly in the aerospace industry. Recent archaeometallurgical studies show that stress corrosion cracking occurred in ancient metallic artifacts. This article describes investigations that revealed definite evidence for SCC in ancient silver and bronze alloys and a probable case of SCC in low-carat (13K) gold. Diagnostic methods included visual inspection, metallography, and fractography.

An advanced, patented probe sensor provides early detection of water infrastructure problems caused by corrosion and harsh atmospheric conditions. Designed to detect graphitization in active pipelines, it identifies areas at risk of major failures early on. By using indirect methods like GIS mapping, in-situ soil resistivity testing, and structure-to-soil potential measurements, high-risk zones can be pinpointed. Once these areas are identified, the probe assesses the severity and depth of graphitization, providing a comprehensive evaluation of the pipeline’s condition. This allows for the implementation of effective corrosion management strategies, including cathodic protection systems, to prevent critical failures. This article describes the sensor system and provides a case study of its use. The technology received the 2024 Engineering Materials Achievement Award from ASM International.

In the quest to improve the reliability of partial penetration welding validation, advanced ultrasonic testing techniques have replaced other less accurate methods. This case study compares weld penetration inspection results from phased array ultrasonic testing and the total focusing method in a rib-to-deck assembly on the top part of an orthotropic steel bridge deck.

Wavelength-dependent or hyperspectral imaging is a novel nondestructive characterization technique in the field of neutron radiography and computed tomography. A dedicated facility named VENUS is currently being built at Oak Ridge National Laboratory to provide these characterization capabilities for academia, industry, and other national laboratories. This feature article describes the VENUS capabilities for materials science and engineering, provides a quick overview of the modes of access of the facility, and illustrates the nondestructive measurements and interpretation of results.

Fire risk in electric vehicle batteries can be reduced by detecting flaws through nondestructive visualization. Industrial computed tomography (CT scanning) combined with advanced software that makes sense of CT-generated images, allows users to measure voids and particle sizes within electrode active material during the research and development phase, detect delamination and contamination during cell manufacturing, analyze electrical connections and electrolyte fill levels, and provide many other quality-assurance functions that were once impractical or even impossible to perform.

Phase coherence imaging is a new approach for processing ultrasonic signals generated during nondestructive testing. This article shows how it compares with amplitude-based focusing methods for detecting hydrogen-related microfissures, creep-induced damage, and stainless-steel weld voids.

Terahertz time-domain spectroscopy is a powerful and nondestructive analytical characterization technique for investigating ceramics, glasses, and composites.

Ultrasound is widely used for nondestructive evaluation, structural health monitoring, acoustic emission, sound navigation ranging, and in sensors for automobiles, medicine, and many other applications. Next-generation, small-form-factor sensors have been achieved through advances in piezoelectric micromachined ultrasonic transducers (PMUTs) that can be positioned on either a flexible polymer or a silicon substrate to form an array. This article describes a materials and design optimization study that used finite element analyses to improve designs for robust and practical PMUT sensor arrays.

Increasing use of nonmetallic materials in wind turbine blades is driving the development of nondestructive microwave test methods.

Ultrasound backscattering enables direct determination of the interface between two materials with different microstructures, including different grain sizes.

Use of radiography to inspect insulated generator components without the need to strip insulation offers advantages over other inspection methods to assess serviceability and need for repair. This article outlines some of the considerations involved in using nondestructive radiography techniques to assess component integrity.

Nondestructive evaluation comprises a large family of specific test disciplines including visual inspection, dimensional metrology, ultrasound, radiography, penetrant tests, magnetic particle tests, leak tests, eddy current tests, potential drop tests, flash and vibrothermography, shearography, acoustic emissions, and many other methods. This article offers an overview of NDE science and discusses some key considerations for choosing specific techniques.

By limiting recombination, passivated emitter and rear cell (PERC) solar cells can provide an absolute efficiency boost of 1%, making their relative efficiency about 7% greater than that of other screen printing methods. This article covers the early stages of the nondestructive and destructive imaging performed to evaluate and enhance the efficiency of PERC solar cells. Electroluminescence images, acoustic images, and scanning electron micrographs were used in this research.

Recent advances in neutron sources and detector technologies enable new contrast mechanisms to determine crystalline information for metal components. This new capability can help validate emerging additive manufacturing processes used to produce parts with complex geometries.

This article provides an update on a three-year three research project by the Center for Heat Treating Excellence aimed at establishing nondestructive techniques for measuring surface hardness and case depth on carburized steels for process verification and control.

Magnetic Barkhausen noise analysis is a nondestructive test method used since the 1980s to evaluate conditions in a variety of steel components. Primary applications include detection of thermal damage induced during grinding and evaluation of case depth in case-hardened parts. This article briefly describes its use for measure case depth and pros and cons of the using the technique for that purpose.

The Center for Heat Treating Excellence (CHTE) at Worcester Polytechnic Institute (WPI) in Massachusetts is conducting a cutting-edge research project aimed at measuring the surface hardness and case depth on carburized steels for process verification and control. The results will enable companies to improve the quality of heat-treated products faster and more cost-effectively. Nondestructive techniques being evaluated initially include eddy current, meandering winding magnetometer (MWM), Barkhausen noise testing, and alternating current potential drop.

Physical cross-sectioning is commonly used on parts to reveal and study their internal features and defects. An alternative technology, acoustic cross-sectioning, produces equivalent results and images for small parts without damaging them. This article describes a new system for acoustic cross-sectioning and presents a case study of its use in integrated circuit analysis.