含脱铁疏松层铁单晶和孪晶产生内应力的分子静力学模拟

Molecular Statics Simulation on Effects of Twin Boundary on Stress Distribution in Ferrite with Porous Layer

采用分子静力学方法,模拟了孪晶界对含有疏松层的铁素体内应力分布的影响。结果表明,单晶试样在弛豫后挠度随表层空位浓度以及疏松层相对厚度的增加而增大。当试样中存在孪晶界时,其弯曲挠度同样随表层空位浓度和疏松层厚度的增大而增加,并且孪晶界距离疏松层越近,挠度越大;当孪晶界距离疏松层较远时,试样弯曲方向改变。孪晶界处会产生拉应力,最大压应力存在于基体和疏松层的分界处;疏松层内总体呈拉应力。

A molecular statics method was used to simulate the effects of twin boundary on the stress distribution in ferrite with porous layer. The results show that the deflection enhances with the increase of the vacancy concentration and relative depth of porous layer in single crystal. With the introduction of the twin boundary in the specimen, the deflection increases with the increase of the relative depth of porous layer and vacancy concentration. The closer the twin boundary is to the porous layer, the greater the deflection will be. The specimen bends oppositely when the twin boundary is relatively far away from the porous layer. The results of the stress distribution show that a large tensile stress exits around twin boundary,and the maximum compressive stress exists at the interface between porous layer and matrix. The tensile stress exits in the porous layer macroscopically.