Microstructure evolution and mechanical properties of an Mg-Gd alloy subjected to surface mechanical attrition treatment
Microstructure evolution and mechanical properties of an Mg-Gd alloy subjected to surface mechanical attrition treatment
复制标题
表面机械磨损处理的Mg-Gd合金的显微组织演变和力学性能
DOI：
10.1016/j.msea.2015.02.009
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发表时间：
2015-04-10
期刊：
影响因子：
6.4
通讯作者：
Ding, W. J.
中科院分区：
文献类型：
--
作者：
Shi, X. Y.;Liu, Y.;Ding, W. J.
室温下通过表面机械磨损处理(SMAT)在Mg-3Gd合金的表层(0-30μm)中生成纳米尺寸的晶粒(约50-100nm)。利用透射电子显微镜研究了纳米晶粒的变形过程和形成机制。结果表明，当位错滑移受阻时，孪晶在塑性变形的初始阶段占主导地位。直到所有的粗晶粒通过孪生相互作用和双位错阵列相交而被分成亚结构时，位错滑移和堆垛层错开始发挥重要作用，通过位错阵列滑移使晶格旋转推动亚晶粒向纳米晶粒转变。动态旋转再结晶是SMAT形成Mg-3Gd合金纳米晶的主要机制，它与剧烈塑性变形过程中通常观察到的迁移再结晶不同。 (C) 2015 Elsevier B.V. 保留所有权利。
Nanometer-sized grains (around 50-100 nm) were generated in the surface layer (0-30 mu m) of an Mg-3Gd alloy by means of surface mechanical attrition treatment (SMAT) at room temperature. The deformation process and the formation mechanism of nano grains were investigated by using transmission electron microscopy. The results show that twinning dominates the initial stage of the plastic deformation when the dislocation slips are obstructed. And till all the coarse grains are divided into substructures by twin-twin interactions and twin-dislocation arrays intersections, dislocation slips and stacking faults begin to play an important role in impelling subgrains to nanograins by lattice rotating through dislocation arrays slipping. Dynamic rotation recrystallization is the primarily formation mechanism of the nanocrystalline of Mg-3Gd alloy by SMAT, which is distinct from the migration recrystallization normally observed in severe plastic deformation process. (C) 2015 Elsevier B.V. All rights reserved.