Outcomes from applying the contour method to EASI-STRESS benchmark specimens

The recently concluded EASI-STRESS project examined a series of benchmarks from a variety different material systems, to illustrate the differences in obtained residual stresses from all applicable measurement techniques. Specifically, heavily plastically deformed ferritic and as-built laser-powder bed fusion stainless steel benchmarks were compared over a wide range of methods. The magnitudes of residual stresses were found to be approaching the respective yield stress of each material system by diffraction techniques. These high residual stress magnitudes, coupled with irregular cross-sections and geometry proved to be difficult candidates for applying the contour method. Two different applications of the contour method on each will be presented and compared with those obtained by diffraction techniques. The specific practices to minimize the impacts of cutting induced plasticity and component fixation during cutting will be presented, along with results obtained. In all cases, the mean stress obtained from the contour method matched those found with neutron and synchrotron x-ray diffraction. These specific implementations of the contour method are intended to illustrate how challenges in technique’s application can be overcome.