RESIDUAL STRESS MEASUREMENT USING TWO-DIMENSIONAL DIFFRACTION SYSTEM

摘要

Two-dimensional diffraction systems, when used for residual stress measurement, have many advantages over the conventional one-dimensional diffraction systems in dealing with highly textured materials, large grain size, small sample area, and weak diffraction. The stress measurement is based on the fundamental relationship between the stress tensor and the diffraction cone distortion. The benefit of the 2D method is that all the data points on diffraction rings are used to calculate stresses so as to get better measurement result with less data collection time. The present paper covers the recent development in the theory and applications of stress measurement using 2D detectors. The topics include true stress-free lattice parameter, anisotropic factor, experimental comparison between conventional method and 2D method, stress measurement with transmission mode diffraction and stress measurement using CCD detector and synchrotron beam.