摘要
研究了铸造ZTC4钛合金表面缺陷对恒ΔK下疲劳裂纹扩展路径、速率、塑性应变的影响。采用高分辨透射X射线三维成像法、扫描电镜、网格法对疲劳裂纹扩展路径、形貌和塑性区进行表征。结果表明,疲劳裂纹扩展路径向缺陷位置偏转,缺陷附近裂纹扩展速率明显增加,表面缺陷与疲劳裂纹相交位置塑性变形量相对较大。
Influence of surface defects on the fatigue crack path,propagating rate and plastic strain under constant ΔK was investigated.The fatigue crack paths,appearance and plastic region were characterized by 3D X-ray tomography,SEM and grid method.The results reveal that the fatigue crack can be deflected towards the surface defects.The fatigue crack rate is increased obviously near the defects,and the plastic deformation is relatively bigger at the intersection location of surface cracks and fatigue cracks.
引文
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