双孔洞排布位置对c轴压缩镁单晶的影响

Influence of the Arrangement of Double Voids on the c-Axis Compressed Magnesium Single Crystal

为探究双孔洞位置排布对于镁及镁合金塑性变形的影响,应用分子动力学方法模拟在300K下含不同排布位置的双孔洞镁单晶c轴压缩模型,结合3种模型的应力-应变曲线、势能曲线、径向分布函数和位错密度曲线,分析不同排布位置双孔洞镁单晶的压缩力学性能和结构演化过程。结果表明:双孔洞镁单晶在与加载方向平行时可承受的压应力峰值和势能峰值以及对应的应变程度最大,与加载方向垂直时次之,当与加载方向呈45°排布时最小,且与c轴呈90°排布的双孔洞镁单晶模型孔洞闭合速率最快。

The molecular dynamics method was used to simulate the c-axis compression model of two voids single crystal magnesium with different arrangement positions at 300 K. Combined with the stress-strain curve, potential energy curve, radial distribution function and dislocation density curve of the three models, the compression mechanical properties and structural evolution process were analyzed. The results show that the maximum compressive stress, peak potential energy and corresponding strain can be tolerated when the single crystal is parallel to the loading direction, the second is perpendicular to the loading direction, and the smallest is 45° arrangement with the loading direction. The double void model with 90° arrangement with c axis has the fastest voids closure rate.