Effects of Shot Peening on High Cycle Fatigue Behavior of Powder Metallurgy and Conventional forms of a Medium Carbon Steel

Author:  M.M.Mirzazadeh
Source:  Conf Proc 2011: ICSP-11 South Bend, IN USA (pgs. 177-182)
Doc ID:  2011029
Year of Publication:  2011
Abstract:  
Abstract Non shot-peened and shot-peened quenched-tempered medium carbon (AISI 1151QT) steel and PM specimens were fatigue tested under fully reversed tension-compression loading conditions to investigate shot peening influence on the high cycle fatigue properties of these steels (N=106-107 ).The results showed that shot peening had beneficial effect on fatigue limit of PM whereas it had detrimental effect on AISI 1151QT. Microhardness profiles indicated that higher amplitude of cyclic softening occurred in shot peened AISI 1151QT than non shot-peened conditions but neither cyclic softening nor hardening was apparent in PM steels. The gradient of compressive residual stresses induced by shot peening was greater than loading stresses. The results show that AISI 1151QT fatigue limit decreased 11-12.0% after shot peening whereas increased 10-14% in PM indicating compressive residual stresses and work hardening played important role. Keywords Shot-peening, fatigue, powder metallurgy (PM), quenched-tempered, carbon steels.