Effect of rare earth elements on deformation behavior of an extruded Mg-10Gd-3Y-0.5Zr alloy during compression
Effect of rare earth elements on deformation behavior of an extruded Mg-10Gd-3Y-0.5Zr alloy during compression
复制标题
稀土元素对挤压Mg-10Gd-3Y-0.5Zr合金压缩变形行为的影响
DOI：
10.1016/j.matdes.2012.10.040
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发表时间：
2013-04-01
影响因子：
8.4
通讯作者：
Zeng, X. Q.
中科院分区：
文献类型：
--
作者：
Mirza, F. A.;Chen, D. L.;Zeng, X. Q.
研究稀土元素对挤压Mg-10Gd-3Y-0.5Zr镁合金室温挤压方向应变硬化行为的影响。这种含re合金的塑性变形行为表现为应变硬化率快速下降至应变水平约4%（阶段a），随后在应变范围从接近4%到接近18%（阶段B）的扩展范围内，线性应变硬化率相当平坦。阶段C表现为失效前应变硬化速率下降。在这种合金中观察到的孪晶程度比在无re挤压镁合金中要小得多。由于稀土元素的加入使得孪晶的形成和位错在较低应变下的滑移更加困难，导致了较弱的晶体织构、细化的晶粒尺寸和第二相颗粒在A阶段的应变硬化率更高。在较高应变下，在B阶段出现相当平坦的线性应变硬化，这可能与位错-孪晶相互作用以及位错/孪晶与第二相颗粒和晶界相互作用产生的位错碎屑和孪晶碎屑（或残余孪晶）有关。(C) 2012 Elsevier Ltd.版权所有。
The aim of this study was to identify the influence of rare-earth (RE) elements on the strain hardening behavior in an extruded Mg-10Gd-3Y-0.5Zr magnesium alloy via compression in the extrusion direction at room temperature. The plastic deformation behavior of this RE-containing alloy was characterized by a rapidly decreasing strain hardening rate up to a strain level of about 4% (stage A), followed by a fairly flat linear strain hardening rate over an extended strain range from similar to 4% to similar to 18% (stage B). Stage C was represented by a decreasing strain hardening rate just before failure. The extent of twinning in this alloy was observed to be considerably less extensive than that in the RE-free extruded Mg alloys. The weaker crystallographic texture, refined grain size, and second-phase particles arising from the addition of RE elements were responsible for the much higher strain hardening rate in stage A due to the increased difficulty on the formation of twins and the slip of dislocations at lower strains, and for the occurrence of quite flat linear strain hardening in stage B at higher strains which was likely related to the dislocation debris and twin debris (or residual twins) stemming from dislocation-twin interactions as well as the interactions between dislocations/ twins and second-phase particles and grain boundaries. (C) 2012 Elsevier Ltd. All rights reserved.