0Cr16 Ni5 Mo不锈钢疲劳性能研究

通过疲劳试验对 0Cr16Ni5Mo不锈钢疲劳性能和海水中的腐蚀疲劳性能进行了研究 ,并对断口特征进行了金相及SEM分析。结果表明 :钢的σ-1 、σ-1SCC 和τ-1 分别为 5 5 0MPa、40 8MPa和 2 85MPa ,σ-1 、τ-1与σb 、σ0 .2 之间符合奥金格公式。不同条件下的疲劳断口特征各异 ,纯旋转弯曲疲劳断口属正常形貌 ,而扭转疲劳断口的扩展阶段疲劳条带不明显 ,这与受力条件复杂有关。海水介质中疲劳开裂具有表面多条裂纹源特征 ,裂纹尖端的应力集中加速裂纹扩展造成腐蚀疲劳强度降低 ,裂纹扩展至断裂符合正常疲劳断裂机理。

Study on Fatigue Properties of 0Cr16Ni5Mo Stainless Steel

Fatigue tests were carried out to investigate the fatigue properties and corrosion fatigue properties in seawater of 0Cr16Ni5Mo stainless steel. Fractographic analysis was conducted through optical microscope and scanning electron microscope. The results show that σ -1 ? σ -1SCC and τ -1 of 0Cr16Ni5Mo was 550MPa?408MPa and 285MPa respectively,the relationship among σ -1 , τ -1 , σ b and σ 0.2 conform to Ojeng formula. The fractographic characteristics varied according to test conditions, of which fractograpy of rotary bending fatigue exhibited normal fracture features, propagation of torsional fatigue constituted no distinct fatigue strips, this was attributed to complicated stress state. Fatigue fracture in seawater was characterized by multi-crack source on specimen surface. The stress concentration at the tip of the crack speeded up the crack propagation, which resulted in the decrease of corrosive fatigue strength. The mechanisms of the crack propagation and the final fracture correspond with the well-known fatigue failure mechanisms.