Influence of shot peening on fatigue durability of decarburized spring steels

Author:  Dalaei, Hoijer, Akerstrom, Karlsson
Source:  Conf Proc 2011: ICSP-11 South Bend, IN USA (pgs. 183-188)
Doc ID:  2011030
Year of Publication:  2011
Abstract:  
ABSTRACT The influence of shot peening on high cycle fatigue behaviour of spring steel was investi-gated. The material studied was a quenched and tempered carbon steel 51SiCr7 (0.55 C, 1.9 Si and 0.9 Mn). Three series of fatigue specimens with zero, 0.15 and 0.50 mm depth of decarburization were produced. Half of the specimens from each series were shot peened, leading to a thickness of the compressed surface layer of about 0.25 mm. The specimens were tested in bending fatigue. A 45% improvement in fatigue limit of the decarburized series was achieved after shot peening. The detail of relaxation of the residual stresses was followed and compared for different series of specimens. KEY WORD Decarburization, fatigue strength, residual stresses, shot peening.