Cailiao Baohu (Aug 2022)
Effect of Composite Shot Peening on the Rotating Bending Fatigue Life of PH13 - 8Mo Steel
Abstract
In order to improve the rotating bending fatigue life of PH13 - 8Mo stainless steel, the surface morphology, surface roughness and fatigue life of samples without shot peening, single shot peening and composite shot peening were tested respectively in the H510, H540 and H550 heat - treated states. Results showed that in the comparison with single shot peening, the fatigue enhancing effect of the specimens treated with composite shot peening in H540 and H550 states was significantly better than that of the specimens in H510 state. Under the condition that σmax=800 MPa and R=-1, the Kt=1 fatigue life of specimens in H510, H540 and H550 states was increased by 0.3, 1.4 and 1.4 times respectively. Compared with single shot peening, the enhancing effect of Kt=2 composite shot peening had better than that of Kt=1. Under the condition that σmax=550 MPa and R=-1, the Kt=2 rotating bending fatigue life was increased by 5.5 times. Shot peening could improve the fatigue life of PH13 - 8Mo steel. The Kt=1 rotating bending fatigue life of the specimens treated with shot peening was at least 1 order of magnitude higher than that of the non - shot peening specimens. Besides, the surface roughness, surface morphology, residual stress field and fatigue life of composite shot peening specimens were all better than that of the specimens treated with single shot peening.
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