Misfit strain induced phase transformation at a basal/prismatic twin boundary in deformation of magnesium
Misfit strain induced phase transformation at a basal/prismatic twin boundary in deformation of magnesium
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DOI：
10.1016/j.commatsci.2019.04.020
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发表时间：
2019-06
影响因子：
3.3
通讯作者：
Peng Chen;Fangxi Wang;Bin Li
中科院分区：
文献类型：
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作者：
Peng Chen;Fangxi Wang;Bin Li
纯镁的塑性变形没有发生六方密排相(HCP)向面心立方相(FCC)的转变。在原子模拟纯镁中孪晶迁移的实验中，观察到了1 0 1‘2孪晶的基面/棱柱状孪晶界(TB)处的可逆hcp→面心立方相变。FCC相是由孪晶和母体之间的局部失配应变引起的。当在基底/棱柱状结核形成面心立方相时，结核迁移暂时受阻。随着应变的增加，fcc通过原子洗牌转变为hcp孪晶。FCC和HCP父代之间的取向关系满足1 1 1 FCC||1 0 1‘0 HCP。在转化过程中，通过剪切和洗牌，将双层棱柱面转化为面心立方的1 1 1密排平面。计算了可逆相变的能垒。
Phase transformation from hexagonal close-packed (HCP) to face-centered cubic (FCC) does not occur in plastic deformation of pure magnesium. In this work, a reversible HCP→ FCC phase transformation was observed at basal/prismatic twin boundary (TB) of 1 0 1¯ 2 twinning mode, in atomistic simulations of TB migration in pure magnesium. The FCC phase was induced by a local misfit strain between the parent and the twin. When an FCC phase was formed at the basal/prismatic TB, the TB migration was temporarily hindered. As the strain increased, the FCC transformed to the HCP twin by atomic shuffling. The orientation relationship between the FCC and the HCP parent satisfies 1 1 1 FCC|| 1 0 1¯ 0 HCP. During transformation, a double-layered prismatic plane was transformed into a 1 1 1 FCC close-packed plane of the FCC by shear and shuffle. The energy barriers for the reversible phase transformation was calculated.