非晶Ti_3Al合金的变形晶化机理的原子模拟

Molecular dynamics simulation of deformation-induced crystallization mechanism in amorphous Ti_3Al alloy

利用分子动力学方法研究了非晶Ti3Al合金拉伸过程中的晶化行为,模拟结果表明局部塑性变形导致非晶合金晶化.从微观结构演化的角度分析了拉伸过程中的晶化机理,局部剪切导致拉伸过程中晶粒发生成核与合并,最终生成的晶粒具有面心立方结构.晶核的生长过程伴随着应力强化现象,非晶相中的纳米晶粒能提高非晶合金材料的强度.

The crystallization of Ti3 Al amorphous alloy during tensile deformation was studied with molecular dynamics. The simulation results show that the crystallization of amorphous alloy is induced by the local plastic deformation. The microstructure evolution was analyzed in the tension process. It is found that the nucleation and growth are induced by the shear localization and the final crystal phase has fcc structure. It is also found that the crystallization process is accompanied by strengthening of the material. The nanocrystal grains embedded in the amorphous phase can enhance the rigidity of the sample.