Existing strain measurement techniques do not offer enough information about how failures occur, so alternative methods are needed. One technique involves using digital image correlation (DIC) to measure full field strain over the entire material surface. DIC works by capturing a series of images throughout a test and analyzing them afterwards.

Recent advances in hardware and software provide materials testers with improved productivity and enhanced capabilities. This article describes some innovations in testing composites and aluminum alloy formability and new capabilities in digital image correlation and testing machine software.

Neutron-based imaging and measurement techniques are an ideal complement to x-ray methods for characterizing additively manufactured materials and components. This article presents examples showing how neutron radiography and residual strain measurements reveal the internal structure and stress distributions in highly engineered turbine blades produced by additive processes. It also discusses the development of neutron characterization tools at ORNL and a recent effort in which they were used to evaluate stress-relief treatments for large-scale metal AM structures.

Researchers at the University of Michigan are investigating the complex heterogeneous phase transformations associated with deformation in shape memory alloys by means of in-situ tensile loading in combination with SEM, EBSD, and digital image correlation. This article describes the general approach and presents and interprets test results.

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.

Digital image correlation data and Bayesian inference used together facilitate rigorous quantification of the uncertainty in material input parameters for finite element simulations of superelastic deformation.

Non-contacting extensometry offers a wide range of benefits in materials tests. Depending on the specific application, non-contacting extensometry may be the only option for strain measurement.

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.

While today's composites encompass a broad and well-established family of materials, the commercial market for high-performance, structural composites has actually existed for well over 30 years. Adoption in the aerospace industry has resulted in a wide range of static test methods offering reliable results. This article reviews some recent innovations in composites testing, including developments related to fatigue testing, high strain rate testing, thermography, and high capacity test systems.

This article series explores the indispensable role of characterization in the development of cold spray coatings. Electron backscatter diffraction (EBSD) is a characterization technique that enables determination of crystal orientations, texture, boundary misorientations and deformation behavior, and bonding mechanism in cold spray coatings.

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.

An in-situ annealing technique combined with electron backscatter diffraction was used to characterize the microstructural evolution of ZE20 magnesium alloy as a function of temperature. This work sets the stage for future experiments to understand and control the recrystallization behavior of commercial alloys.

High-speed, high-fidelity techniques used to analyze texture and dislocation content enable greater understanding of the influence of texture on deformation of titanium alloys than previously possible. This article describes a study in which specimens were examined using graphical slip band analysis to understand the influence of microstructure, alloy content, and loading orientation on the surface deformation response of titanium.

Because electron backscatter diffraction is a surface-sensitive technique, preparing the sample surface so that it is smooth and free of defects is crucial to successful analysis. Supplementing hand polishing with ion milling provides a superior surface finish free of operator or technique-related errors, thus enabling a high-confidence EBSD examination of the microstructure of even the most complex materials.

Computer modeling is used in the design and development stages of induction hardening to optimize the process and to improve component quality including hardness, beneficial stress distributions, and reduced distortion.

This article describes research at Los Alamos National Laboratory that is aimed at building a coupled experimental and computational methodology that supports the development of predictive damage capabilities by: (1) capturing real distributions of microstructural features from real material and implementing them as digitally generated microstructures in damage model development, and (2) distilling structure-property information to link microstructural details to damage evolution under a multitude of loading states.

Despite decades of research, fundamental questions still exist regarding the role of microtexture on the deformation, fatigue, and fracture behavior of titanium alloys. This article describes the microstructural evolution processes that result in microtexture formation, while Part II of this series will further elaborate on the effects of microtexture on deformation behavior.

This article explains how SEM, TEM, and atom probe tomography are being used in the development of additively manufactured high-entropy alloys (HEAs), revealing critical features such as anisotropic microstructure and metallurgical defects. It also discusses ongoing efforts to improve the predictability and analysis of HEA microstructure using data-driven approaches.

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.

New research explores a zirconia-based shape memory ceramic that exhibits a unique type of electrically triggered martensitic transformation.