Investigation of Fatigue Crack Growth Behavior on the Shot Peened Carbon Steel by Residual Stress Relaxation

Author:  J.-C. Kim, S.-K. Cheong and H. Noguchi
Source:  Conf Proc 2014: ICSP-12 Goslar, Germany (pgs.43-48)
Doc ID:  2014048
Year of Publication:  2014
Abstract:  
The objective of this study was to investigate the fatigue crack growth behavior on the shot peened (SP) carbon steel during the fatigue test. In general, the compressive residual stress (CRS) induced by SP is the most influential parameter that determines the fatigue strength of SP materials. However, there is some argument that the induced CRS can be relaxed by thermal or mechanical loadings, therefore stability of CRS during cyclic loads is a great important aspect for SP process. In this regard, it is necessary to understand their influence on the fatigue crack formations, quantitatively. In this study, the evaluations of fatigue crack growth during the fatigue life associated with residual stress relaxations on the properties of a material were considered. To this end, rotating bending fatigue tests were carried out to introduce the mechanical loadings, and quantitative measurements of the residual stress were made by X-ray diffraction (XRD) technique, and the plastic replication technique was chosen for the crack growth analysis. This presentation discussed the fatigue crack growth behavior by redistributions of induced CRS in detail.