Residual stress measurement of low temperature plasma surface alloyed layer using X-ray diffraction techniques

X-ray diffraction (XRD) techniques including stress measurement were applied to untreated, low temperature plasma nitrided and low temperature plasma carburised AISI 304 austenitic stainless steels treated at 425°C for 12 h in H₂/N₂ and H₂/CH₄ gases respectively. Relationships between surface microhardness and XRD peak broadening were established. The results also showed that both surface treated layers were under a compressive residual stress. The compressive residual stresses of the low temperature plasma nitrided and the low temperature plasma carburised layers were 2·19 and 1·58 GPa.