Influence of Layer Removal Methods in Residual Stress Profiling of a Shot Peened Steel using X-ray Diffraction

摘要

For X-ray diffraction measurement of depth profiles of residual stress, step-wise removal of materials has to be done to expose the underneath layers to the X-rays. This paper investigates the influence of layer removal methods, including electro-polishing in two different electrolytes and chemical etching, on the accuracy of residual stress measurement. Measurements on two shot-peened steels revealed large discrepancy in subsurface distributions of residual stress obtained with the respective methods. Especially, the chemical etching yielded much lower subsurface compressive stresses than the electro-polishing using a so called All electrolyte. The difference was explained by the influence of the different layer removal methods on the microscopic roughness.