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.

Accurate measurement of retained austenite levels is important in the development and control of a heat treatment process.

This unique testing method offers economic benefits, sustainability advantages, and the potential to slash the time required to develop new alloys and processing recipes.

Various methods are available to evaluate the behavior of viruses on material surfaces, an important area of research for determining how long a virus can live on an inanimate object, and learning how to design and develop advanced antiviral materials.

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

Advanced instrumentation combined with effective test procedures gives manufacturers an edge in measuring and analyzing welds.

This article addresses work to develop core technology for high pressure die casting in order to enable high volume and low-cost manufacturing of lightweight automotive components with complex hollow structural shapes. Although experimental verification of the concept using a part with simplified geometry looks promising, the technique requires further testing using commercial components with internal cavities of complex geometry.

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.

Residual gas analysis shows that vacuum furnaces with graphite hot zones are more economical than all-metal designs and are capable of producing contamination-free surfaces.

Emissivity is a term used to define the ability of a surface to emit and absorb radiation. At any given temperature, the emissivity of a body (or surface) equals its absorptivity. Development work on a vacuum carburizing process revealed the need to better understand the effect of workload surface emissivity and the proper use of dummy thermocouple test blocks. This article reports on the findings from this research effort.

To meet the rigorous demands of next-generation computer technology, new approaches to nondestructive measurement for early stage, temperature dependent materials characterization are needed. Terahertz spectroscopy bypasses the limitations of other characterization techniques by enabling nondestructive measurement under variable temperature and high magnetic field conditions.

Accurate multi-component thickness and moisture data is critical to the productivity and efficiency of producers of plastic films, extrusion coatings, blown films, and nonwoven fabrics. Collecting this data on production lines in real-time ensures that raw materials are not wasted and that all products meet relevant specifications. This article describes several different noncontact online analysis techniques, which primarily measure thickness by passing either nuclear or electromagnetic radiation through the web and measuring its absorption patterns via a detector on the other side of the material.

Ductile fracture toughness testing is useful for evaluating a material’s structural integrity. This article briefly reviews three widely used J-integral vs. crack growth resistance (J-R) curve test methods for metals: elastic unloading compliance, normalization, and direct current potential drop. The J-Integral calculation is the same in all three methods, with differences primarily involving crack size measurements.

This article describes traditional methods for identifying particle contamination in manufacturing processes as well as a new alternative method that uses scanning electron microscopy combined with energy-dispersive x-ray spectroscopy. The new system provides efficient, accurate microanalysis to identify the size, shape, and chemical composition of particles. A case study in automobile manufacturing is presented.

Automobile performance and passenger safety both rely on sound spot welds in advanced high-strength steels. A new, high-frequency ultrasonic matrix phased array probe performs nondestructive inspection of these welds, saving time and cost.

Several industries are now expanding robot integration beyond production tasks into new areas such as testing, where it has been shown to increase throughput and eliminate operator influence.

This article discusses the development and use of a nondestructive evaluation (NDE) method that allows researchers to compare surface crystallographic orientations before and after mechanical testing to determine the impact of surface orientation on material response. Two gage samples were tested, one rectangular (Ti-Al), the other round (IN100). The samples were placed in a SEM equipped with an EBSD detector and a motorized fixture that rotates the test piece as EBSD and imaging data are collected. Inverse pole figure maps of both gage samples are presented.

A microscale fatigue testing technique for characterizing mechanical response and relating it to microstructure promises to improve fatigue life prediction for turbine engine components.

Raman spectroscopy is an indispensable tool in laboratories conducting research in the nascent field of carbon nanomaterials. It provides comprehensive information about the structure and layer thickness of graphene samples with high levels of sensitivity, stability, and control.

This article reviews the measurement physics of macro and micro Vickers indentation testing and the factors that determine measurement precision and repeatability. Study results show that when force loads of less than 100 gf are used, it is difficult for operators to precisely determine the position of the indenter tip, leading to various measurement errors. These errors explain the data anomalies reported in the literature for low-load Vickers hardness testing, which are often incorrectly attributed to material characteristics.