Effect of temperature and strain rate on the tensile properties related to hot cracking of Csf/AZ91D composites
Effect of temperature and strain rate on the tensile properties related to hot cracking of Csf/AZ91D composites
复制标题
DOI：
10.1016/j.msea.2013.12.056
复制
发表时间：
2014-02
期刊：
影响因子：
6.4
通讯作者：
Jian Liu;L. Qi;Peng Liu;Juntao Guan;Ji-ming Zhou
中科院分区：
文献类型：
--
作者：
Jian Liu;L. Qi;Peng Liu;Juntao Guan;Ji-ming Zhou
采用半固态部分重熔拉伸试验方法，测定了Csf/Mg复合材料在刚低于和高于初熔温度时不同应变速率下的极限拉伸强度（σUTS）和断裂应变（εf）。结合损伤机理的讨论，分析了σ UTs和ε f的变化规律。与σUTS相比，ε f对温度和应变速率的敏感性更高。ε f在部分熔化起始温度和低应变速率下达到最大值，当液相含量增加到6%时，晶界和界面处的液相在变形中起主导作用，复合材料表现出很低的塑性。孔洞的萌生位置与试验温度和应变速率密切相关，裂纹扩展的有利方向与应变速率密切相关。
The ultimate tensile strength (σUTS) and fracture strain (εf) of Csf/Mg composites at temperatures just below and above the incipient melting temperature with different strain rates were determined by modified semi-solid tensile tests using a partial remelting approach. The variations ofσUTSandεfwere analyzed combining the discussion of damage mechanism. It was concluded thatεfis more sensitive to the temperature and stain rate compared withσUTS. The maximumεfwas achieved at the onset temperature for partial melting and at low strain rate, when the liquid fraction rose to 6%, the liquid phase at grain boundaries and interfaces played a dominant role in the deformation, and the composites exhibited very low ductility. The cavity initiation sites were closely related to the test temperature and strain rate, and the favored direction of crack propagation was highly dependent upon the strain rate.