Calculation of residual stresses in case-hardened SAE5115 steel cylinders

The development of stresses for five differently case-hardened SAE5115 steel cylinders with variable surface carbon mass contents c_S and carburization depths CD during single hardening are calculated. The carbon profiles and the retained austenite distributions in the near-surface material areas are approximated in a stepwise manner. Exemplarily, in the middle plane of cylinders with c_S = 0.5 % C (CD = 0.07 mm) and 1.1 % C (CD = 0.2 mm), the local axial stresses at the surface, at four near-surface points and in the core are described during the hardening process up to temperature balance. The influence of c_S and CD on the surface tangential residual stress values along the casing of the cylinders is outlined. Also the depths distributions of the tangential residual stresses in the middle plane are presented for differently carburized cylinders. At c_S = 1.1 % C = const. the distance of maximum compressive residual stresses beneath the surface as well as the thickness of the compressed surface and the distances with the largest tensile residual stresses increase with increasing CD.