植入铸造317L不锈钢在Hank’s模拟体液中腐蚀疲劳裂纹的萌生和扩展

THE INITIATION AND PROPAGATION BEHAVIOR OF CORROSION FATIGUE CRACKS FOR CAST 317L STAINLESS STEEL IN HANK'S PHYSIOLOGICAL SOLUTION

利用往复弯曲疲劳试验机和SEM研究了铸造317L不锈钢材料在Hank’s模拟体液中的腐蚀疲劳裂纹的萌生和扩展行为.铸造317L不锈钢具有晶间腐蚀敏感性,首先在晶界上孕育萌生初始疲劳裂纹,继而扩展,形成主裂纹,发生断裂.在断口上产生了疲劳辉纹,二次裂纹和疲劳台阶.

The initiation and propagation behaviors of corrosion fatigue cracks for cast 317L stainless steel in Hank's physiological solution were studied by using reciprocating bending fatigue test machine and SEM. The initial fatigue micro-cracks first engendered in granular boundaries due to the susceptibility to the intergranular corrosion and continued to propagate under the co-effect of stress and corrosion medium. The stainless steel frac-tured because one of initial cracks became the main crack and propagated quickly、Fatigue striations, secondary cracks and fatigue steps engendered on the fracture surface of cast 317L stainless steel.