摘要：30 H-shaped welded beam specimens of Q345 and QSTE700 steels were tested in h igh cycle fatigue tests. Methods of finite element analysis, group method and microstructure observation were employed to investigate the fatigue propert ies of two kind of material s mentioned above in this work. The results show that the H-type welded specimens of different materials varied obvious ly in both their fatigue strengths and initial cracking locations. The f racture related to the relationship between the yield strength of the base metal and that of the weld ing zone . Welding, especially repair weld ing , ha s a apparent influence on the fatigue characteristics of Q345 steel.
