FATIGUE ANALYSIS OF TENSION SHEAR SPOT WELDS BASED ON MATERIAL PROPERTY GRADIENT

摘要

Fatigue life analysis was carried out on spot welds, taking into the effect of welding process on local metal mechanical properties within heat affected zone.Considering the relationship between material strength and cyclic stress strain parameters,life prediction with Pollard's equation gave results with errors in 2 factors,as well as Barkey's data.Experimental results were further studied with Manson-Coffin damage equation.Results showed that the metal mechanical properties gradient have implicit effect on crack initiation site,cannot be neglected in fatigue life prediction.