Welding influence on fatigue properties of two automobile steels
30 H-shaped welded beam specimens of Q345 and QSTE700 steels were tested in high cycle fatigue tests. Methods of finite element analysis, group method and microstructure observation were employed to investigate the fatigue properties of two kind of materials mentioned above in this work. The results show that the H-type welded specimens of different materials varied obviously in both their fatigue strengths and initial cracking locations. The fracture related to the relationship between the yield strength of the base metal and that of the welding zone. Welding, especially repair welding, has a apparent influence on the fatigue characteristics of Q345 steel.