OS04F125 Modern and Historical Engineering Concerns Investigated by Neutron Diffraction

Diametral compression test method to analyse relative surface stresses in thermally sprayed coated and uncoated circular disc specimens

“…Considering thermal spray coating formation, residual strain (or stresses) are formed within the coating and substrates due to many processes (quenching stress, peening effect, deposition temperature, lamella structure) and phase differences [13][14][15][16][17][18]. However, traditionally, as presented by Godoy et al [19], residual stresses mainly arise from two different sources: (a) shrinkage of the spray particles after solidification (primary cooling process), and (b) differences between the coating and substrate thermal expansion coefficients (secondary cooling process).…”

“…Non-destructive (laboratory X-ray, synchrotron Xray, neutron, Raman spectroscopy, digital image correlation, photoluminescence piezospectroscopy), semi-destructive (hole-drilling & ring-coring, layer removal, focused ion beam milling, indentation), and miscellaneous other (curvature, modified layer removal, material removal) approaches have been adapted to experimentally evaluate the residual stress fields in thermal spray coatings. The measured values of stress in the coating-substrate system can be sensitive to the stress measurement technique, which in turn can influence the predicted life of coated components [13][14][15][16][17][18]. However, this study will consider a diametral compression destructive testing method on thermally sprayed and uncoated circular disc specimens to compare the surface relative stresses.…”