RESIDUAL STRESS MEASUREMENT OF A FERRITIC BEAD ON PLATE BENCHMARK TEST SPECIMEN USING THE CONTOUR METHOD

摘要

This paper presents new measured residual stress data for a ferritic weld bead on plate benchmark specimen. The contour residual stress measurement method was applied because it could provide an informative map on the plane of interest capable of quantifying local variations in residual stress associated with phase transformations. The quality of the contour cut was optimised by carrying out initial cutting trials to tune the electro-discharge machining cutting parameters. The risk of plasticity during the cutting procedure was minimised by using an "embedded crack" contour cutting configuration, clamping with fitted bolts and a large diameter cutting wire in order to reduce the crack opening and stress concentration at the cut tip. The results of the contour method measurement are in reasonable overall agreement with published stresses measured by neutron diffraction. However, certain features in the results suggest that significant plasticity did occur during the contour cut despite the specific measures taken to minimise this effect.