Engineering Related Neutron Diffraction Measurements Probing Strains, Texture and Microstructure

Neutron diffraction has been used for engineering applications for nearly three decades. The basis of the technique is powder diffraction following Bragg’s Law. The measured diffraction patterns provide information about internal strains, texture and microstructure, which can be deduced from the peak positions, peak intensities, and peak widths, respectively. Most structural materials are anisotropic on the grain level and thus the effects of intergranular strains must be considered, and combining the neutron diffraction measurements with polycrystal deformation modeling has proven invaluable in determining the overall stress and strain values of interest in designing and dimensioning engineering components. Furthermore, the combined use of diffraction measurements and polycrystal deformation modeling has provided a unique tool for elucidating basic material properties, such as critical resolved shear stresses for the active deformation modes and their evolution as a function of applied deformation.