Counter Method as X-Ray Microbeam Diffraction Technique and its Application to Stress Concentration Problems

In the present paper, the applicability of the counter method for stress measurement as one of the X-ray microbeam diffraction techniques is discussed. The stress can be measured at a local area of 330μ in diameter for Cr powder and 450μ for HT60 steel by using the crystal oscillation X-ray microbeam diffraction technique. The stress measured by this method agrees with the applied stress, and therefore, this method is suitable for both residual and applied stresses. As an example of the application of the method, internally notched plates were stretched and the stress distributions in the vicinity of notch tips were measured. The stress distributions obtained experimentally at the notch tips were similar to those calculated by the finite element method in the elastic regime. In the plastic regime, however, there was a slight discrepancy between them because of the influence of the yielding conditions of specimens. It is concluded that the counter method is a very effective mean for the studies of stress concentration problems and its application to the field of strength of materials is promissing.