EFFECT OF MICROSTRUCTURE ON FATIGUE CRACK INITIATION OF SHOT PEENED COPPER AND BRASS
EFFECT　OF　MICROSTRUCTURE　ON　FATIGUE　CRACK　INITIATION　OF　SHOT　PEENED　COPPER　AND　BRASS

The effect of microstructure on fatigue crack initiation was considered in the shot peened surface layer by eliminating the influence of compressive residual stress. Results indicate that the drastically deformed structure by shot peening would keep the dislocations from moving out of the surface and hold the dislocations inside the cell structure of copper or the palling structure of brass. The fatigue damage of intrusion and extrusion type could thus be depressed and the fatigue life is enhanced.