Very-high-cycle fatigue crack initiation and propagation behaviours of magnesium alloy ZK60
Very-high-cycle fatigue crack initiation and propagation behaviours of magnesium alloy ZK60
复制标题
ZK60镁合金甚高周疲劳裂纹萌生及扩展行为
DOI：
10.1080/02670836.2017.1407556
复制
发表时间：
2018-01-01
影响因子：
1.8
通讯作者：
Chen, Qiang
中科院分区：
文献类型：
--
作者：
He, Chao;Liu, Yongjie;Chen, Qiang
本文的目的是评估镁合金（ZK60）的超高周疲劳（VHCF）行为。结果表明，疲劳裂纹起始于由许多分布的刻面组成的区域，而早期裂纹扩展的区域的特征在于平行的痕迹，基于断口分析。裂纹萌生区周围形貌的显著差异是由于变形孪晶与裂纹尖端塑性区之间的相互作用造成的。此外，疲劳裂纹扩展速率周围的裂纹萌生位置也估计基于一个修改的村上模型。结果表明，疲劳裂纹的形成阶段对VHCF区的疲劳失效机制有重要影响。
The aim of this paper is to assess the very-high-cycle fatigue (VHCF) behaviour of a magnesium alloy (ZK60). Results indicate that the fatigue crack initiates from an area consisting of many distributed facets, while the region of early crack propagation is characterised by parallel traces, based on a fractographic analysis. The significant differences in morphology around the crack initiation area result from the interaction between the deformation twinning and the plastic zone at the crack tip. In addition, the fatigue crack propagation rate around the crack initiation site is also estimated based on a modified Murakami model. It is found that the formation stage for the fatigue crack is of great importance to the fatigue failure mechanism in the VHCF regime.