Fatigue crack initiation of magnesium alloys under elastic stress amplitudes: A review-猫眼课题宝

弹性应力幅下镁合金疲劳裂纹萌生：综述

DOI：

10.1007/s11465-018-0482-1

发表时间：

2019-03

期刊：

Front. Mech. Eng

影响因子：

通讯作者：

中科院分区：

其他

文献类型：

作者：

B. J. WANG;D. K. XU;S. D. WANG;E. H. HAN

镁（Mg）合金最有利的特性是它们的密度，与传统金属材料相比密度较低。镁合金作为最轻的金属结构材料，在交通运输和航空航天工业中具有很大的应用潜力。镁合金在弹性应力幅作用下的疲劳性能评价对于保证镁合金的使用安全性和可靠性具有重要意义。由于镁及镁合金具有六方密排结构，其疲劳裂纹萌生与孪晶和基滑移变形机制密切相关。然而，对于含有缩松和夹杂物的镁合金，疲劳裂纹将优先在这些缺陷处萌生，显著降低疲劳寿命。本文综述了镁合金疲劳裂纹萌生机制的一些基本方面，包括：1）铸态镁合金的疲劳裂纹萌生; 2）显微组织对变形镁合金疲劳裂纹萌生的影响; 3）热处理对疲劳裂纹萌生机制的影响。最后，对镁合金疲劳裂纹萌生机理研究中存在的问题和今后的研究方向进行了展望。

The most advantageous property of magnesium (Mg) alloys is their density, which is lower compared with traditional metallic materials. Mg alloys, considered the lightest metallic structural material among others, have great potential for applications as secondary load components in the transportation and aerospace industries. The fatigue evaluation of Mg alloys under elastic stress amplitudes is very important in ensuring their service safety and reliability. Given their hexagonal close packed structure, the fatigue crack initiation of Mg and its alloys is closely related to the deformation mechanisms of twinning and basal slips. However, for Mg alloys with shrinkage porosities and inclusions, fatigue cracks will preferentially initiate at these defects, remarkably reducing the fatigue lifetime. In this paper, some fundamental aspects about the fatigue crack initiation mechanisms of Mg alloys are reviewed, including the 3 followings: 1) Fatigue crack initiation of as-cast Mg alloys, 2) influence of microstructure on fatigue crack initiation of wrought Mg alloys, and 3) the effect of heat treatment on fatigue initiation mechanisms. Moreover, some unresolved issues and future target on the fatigue crack initiation mechanism of Mg alloys are also described.