Relaxation of Shot Peening Induced Residual Stresses in Quenched and Tempered Steel AISI 4140 Due to Uniaxial Cyclic Deformat

Author:  Schulze, Lang, Vohringer, Macherauch
Source:  Conf Proc: ICSP-6, (p.403-412)
Doc ID:  1996086
Year of Publication:  1996
Abstract:  
As a consequence of stess and total strain controlled cyclic deformations the fatigue lives of quenched and tempered specimens of the steel AISI 4140 (German grade 42CrMo 4) are significantly higher for shot peened specimens that for unpeened ones at high numbers of cycles to failure. Shot peening also influences the cyclic deformation behavior. The changes of shot peening induced superficial residual stresses during stress and total strain controlled experiments are investigated with respect to the cyclic deformation. At half of the number of cycles to crack initiation, a correlation independent of the experimental procedure exists between the remaining superficial residual stresses and the apparent plastic strain amplitudes.