The Effect of ECAP Temperature on the Microstructure and Properties of a Rolled Rare Earth Magnesium Alloy
The Effect of ECAP Temperature on the Microstructure and Properties of a Rolled Rare Earth Magnesium Alloy
复制标题
ECAP温度对轧制稀土镁合金组织和性能的影响
DOI：
10.3390/ma12091554
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发表时间：
2019-05-01
期刊：
影响因子：
3.4
通讯作者：
Tian, Liang
中科院分区：
文献类型：
--
作者：
Tan, Yun;Li, Wei;Tian, Liang
采用等通道转角挤压（ECAP）技术，对不同温度下的Mg-2 Y-0.6Nd-0.6Zr合金进行了沿着BC（每道次ECAP后试样反方向旋转90 °）变形。通过显微组织分析，确定了变形温度和预变形量对镁合金显微组织的影响。利用X射线衍射（XRD）和电子背散射衍射（EBSD）研究了Mg-2 Y-0. 6 Nd-0. 6 Zr合金经等通道角变形后的滑移系和织构变化。结果表明，经过7道次轧制，Mg-2 Y-0.6Nd-0.6Zr合金的晶粒尺寸细化到22 μ m左右，滑移主要以圆柱形滑移和锥形滑移为主。在340 ℃下进行一次ECAP后，内部平均晶粒尺寸显著减小至11 μ m，柱状衍射强度明显减弱，棱锥衍射强度增强。EBSD极图分析表明，轧制Mg-2 Y-0.6Nd-0.6Zr合金的ECAP变形后，基体织构由24.31弱化为11.34。力学性能测试结果表明，当变形温度为340 ℃时，轧制Mg-2 Y-0. 6 Nd-0. 6 Zr合金的抗拉强度和伸长率达到最大值。
Deformation of an as-rolled rare earth Mg-2Y-0.6Nd-0.6Zr alloy, at different temperatures, was carried out along the BC (90 degrees anticlockwise rotation of the samples after each ECAP pass) route by equal channel angular pressing (ECAP). The effects of the deformation temperature and the predeformation on the microstructure of the magnesium alloy were determined by the microstructure examination. The slip systems and texture change of the Mg-2Y-0.6Nd-0.6Zr alloy were investigated by X-ray diffraction (XRD) and electron backscattered diffraction (EBSD), after equal channel angular deformation. The results showed that after seven passes of rolling, the grain size in the Mg-2Y-0.6Nd-0.6Zr alloy was refined to approximately 22 mu m and the slip occurred mainly by a cylindrical slip and a pyramidal slip. After one pass of ECAP at 340 degrees C, the internal average grain size was significantly reduced to 11 mu m, the cylindrical diffraction intensity clearly weakened, and the pyramidal diffraction intensity increased. EBSD pole figure analysis revealed that the base texture of the rolled Mg-2Y-0.6Nd-0.6Zr alloy weakened from 24.31 to 11.34 after ECAP. The mechanical properties indicated that the tensile strength and elongation of the rolled Mg-2Y-0.6Nd-0.6Zr alloy reached maximum values, when the deformation temperature was 340 degrees C.