Effect of crystal orientation on the mechanical properties and strain hardening behavior of magnesium alloy AZ31 during uniaxial compression
Effect of crystal orientation on the mechanical properties and strain hardening behavior of magnesium alloy AZ31 during uniaxial compression
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DOI：
10.1016/j.msea.2011.12.013
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发表时间：
2012-02
期刊：
影响因子：
6.4
通讯作者：
Bingshu Wang;R. Xin;G. Huang;Qing Liu
中科院分区：
文献类型：
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作者：
Bingshu Wang;R. Xin;G. Huang;Qing Liu
研究了初始织构对AZ31镁合金力学性能和应变硬化行为的影响。挤压和热轧AZ31圆柱形试件沿不同方向压缩，压缩轴(C)垂直或平行于挤压方向(ED)或板材法向(ND)，分别称为C⊥ED、C//ED、C⊥ND和C//ND试件。压缩试验在室温下进行，应变速率为0.01s−1。结果表明，屈服强度和应变硬化率相对于初始织构具有高度的各向异性。只有少量的双胞胎才能诱导显著的屈服行为。当初始晶向不利于{101‘2}孪晶时，应变硬化率逐渐降低。当初始晶向有利于{101‘2}孪晶时，应变硬化行为表现出三个不同的阶段。提高应变硬化率(对应于阶段II)的主要原因是织构强化，它通过{101‘2}孪晶将晶粒取向转变为硬取向。第二阶段的长度主要与有利于{101‘2}孪晶的颗粒体积分数有关。
The effect of initial texture on the mechanical properties and strain hardening behavior of AZ31 magnesium alloy has been investigated. Cylindrical specimens of extruded and hot rolled AZ31 are compressed along different directions, with the compression axis (C) perpendicular or parallel to the extrusion direction (ED) or the sheet normal direction (ND), referred to as C⊥ED, C//ED, C⊥ND and C//ND specimen, respectively. The compression tests are conducted at room temperature with a strain rate of 0.01s−1. The results indicate that the yield strength and the strain hardening rate are highly anisotropic with respect to the initial texture. The significant yield behavior can be induced by only a small volume of twins. When the initial grain orientations are unfavorable for {101¯2} twinning, the strain hardening rate decreases gradually. When the initial grain orientations are favorable for {101¯2} twinning, the strain hardening behavior exhibits three distinct stages. The main contribution to increasing strain hardening rate (corresponding to the stage II) results from texture strengthening, which rotates grain orientations into hard orientations by the {101¯2} twinning. The length of the stage II is predominantly related to the volume fraction of grains which are favorable for {101¯2} twinning.