SEM IN SITU OBSERVATIONS TO THE EFFECTS OF INCLUSIONS ON INITIATION AND PROPAGATION OF THE LOW CYCLIC FATIGUE CRACK IN SUPER STRENGTH STEEL
夹杂物对超高强度钢低周疲劳裂纹萌生及扩展影响的原位观测

SEM in situ observations for the effects of inclusions on the fatigue crack initiation and propagation behaviors of super strength steel indicate that the inclusion size and shape affect not only on the fatigue crack initiation location but also on the crack growth behavior. At the same time, the effects of inclusions on the fatigue crack initiation are discussed by finite element method (FEM) analysis. The critical size of inclusion in low cyclic fatigue crack propagation is proposed and the influence of fatigue crack growth rate is estimated.