Stability of residual stresses in longitudinally and transversely deep rolled sintered iron under quasistatic and cyclic loading

Abstract

Abstract The residual stresses in flat coupons of sintered iron (ASC100.29) deep rolled on both surfaces were studied in the as-rolled condition and upon quasistatic or cyclic bending. In the as-rolled condition, the stresses are compressive and exhibit a clear orientation dependence with respect to the rolling direction. Also, a significant difference between the primarily and finally deep rolled surfaces is observed, which can be attributed to the effects of specimen bending occurring during the deep rolling process. The evolution of the residual stresses during fatigue is partly counter-intuitive: in transversely deep rolled specimens, an increase in compressive residual stresses in the transverse direction is observed within the very first loading cycle. Possible reasons for this unexpected effect are discussed.