Influence Of Shot Peening Onthe Cyclic Deformation Behaviour Of The Steel 42 Crmo 4 In A Normalized State

Author:  Ebenau, Eifler, Vohringer, Macherauch
Source:  Conf Proc: ICSP-4, (p.337-346)
Doc ID:  1990039
Year of Publication:  1990
Abstract:  
The cyclic stress-strain behaviour of a normalized 42 CrMo 4 (A1S1 4140) was investigated under push-pull and cyclic bending loading (R = -1). For push-pull loading cylindrical specimens were used. The cyclic bending was realized with flat specimens. The push-pull tests were carried out under stress as well as total-strain control. Cyclic bending was performed under total-strain control. The differences in the cyclic deformation curves [E(a,p)-N-curves] of unpeened and shot peened specimens are significant. For N > 19 cycles, the plastic strain amplitudes of shot peened specimens are smaller than those of unpeened ones. As a consequence, the number of cycles to crack initiation and failure for shot peened specimens increases in push-pull as well as cyclic bending tests. For the different kinds of loading, the cyclic stress-strain curves are presented and compared. In this context, the changes of the macro residual stresses as a function of the number of cycles are discussed. The influence of the type of loading (push-pull or cyclic bending) on the E(a,p)-N-curves and the cyclic stress-strain curves, respectively, are also modelled and discussed. Descriptors: Push-pull test; Cyclic bending test; Stress-control; Total strain-control; Cyclic deformation curves; Cyclic stress-strain-curves; Macro residual stresses