非晶层对单晶锗纳米切削影响的分子动力学研究

为探究非晶层结构对单晶锗纳米切削机制和力学特性的影响,采用分子动力学方法模拟不同非晶层厚度的非晶-晶体层状结构(A-C模型)的纳米切削过程.对纳米加工中切削力波动规律,应力状态,亚表面损伤和材料去除等关键问题进行分析.结果 表明:非晶锗(A-Ge)厚度的增加使得切削力和应力减小,切削温度升高;材料的可塑性随着A-Ge厚...

Molecular Dynamics Study on the Influence of Amorphous Layer on Single Crystal Germanium Nano-cutting

Composite structure with amorphous layer and crystalline substrate is important for nano-machining. In order to study the influence of amorphous layer structure on the nano-cutting mechanism and mechanical properties of single crystal germanium (Ge), molecular dynamics (MD) simulations were carried out on the nano-cutting process of amorphous-crystalline layered structure (A-C model) with different amorphous layer thicknesses. Cutting force fluctuation, stress status, subsurface damage characteristics and material removal, which are the key issues in nano-machining were analyzed. The result shows that as the thickness of amorphous germanium (A-Ge) increases, the cutting force and stress decrease, and the cutting temperature increases. The plasticity of the material is enhanced as the thickness of A-Ge increases, which is due to the softening of A-Ge when the cutting temperature rises. When the thickness of A-Ge is the same as the cutting depth, the material has lower subsurface damage and higher material removal rate, so it has excellent mechanical properties.