Stress measurement method using x-ray diffraction analysis

摘要

A stress of a c-axis-oriented specimen (10) of a tetragonal polycrystal is measured using X-ray diffraction under the assumption of a plane stress state. An X-ray optical system is set in the location of phi = 0 DEG , 45 DEG or 90 DEG . An X-ray (16) diffracted at a crystal plane (the direction of the normal thereto is the direction of an angle of psi ) with the Miller indices (hk1) is detected. A diffraction angle &thetas; in a strain state is measured in the vicinity of a Bragg's angle &thetas;0 in a non-strain state. Strains s with respect to a plurality of psi are calculated from the difference between the measurement values &thetas; and the Bragg's angle &thetas;0. Specific stress calculation formulae are determined with respect to the tetragonal system having the Laue symmetry 4/mmm. The stress is calculated from the slope of the linear line of plotted measurement results.