A feasibility study on X-ray stress measurement with CdTe pixel detector

In this paper, we proposed a double exposure method using synchrotron white X-rays (DEM-WX) to measure strains of coarse-grained materials, and examined its feasibility. The X-ray diffractions were measured by a CdTe pixel detector. The CdTe pixel detector can resolve photon energy by changing a threshold voltage. Calibrating each pixel of the detector using characteristic X-rays of Pb and W foils, the images by threshold X-ray energy were obtained. The difference image, which is like a diffraction image with mono-chromatic X-rays, could be calculated by the difference between the images by the threshold X-ray energy. The material of the bending specimen was an austenitic stainless steel with a grain size of 300 µm. The strains of the bending specimen were measured using the DEM-WX, and the results corresponded to the applied strains measured by the strain gauge. (author)