纳米磨削单晶和多晶3J33的分子动力学仿真

Molecular Dynamics Simulation of Monocrystalline and Polycrystalline 3J33 in Nano Grinding

采用Voronoi算法构造多晶体3J33模型,再采用分子动力学(molecular dynamics,MD)实现单晶和多晶3J33的纳米磨削仿真,利用嵌入式原子势能(embeded atomic momentum,EAM)和Morse势函数对工件内部以及工件和磨粒之间的原子作用力进行计算。研究了单晶和多晶在不稳定和稳定两个阶段下纳米磨削过程的特点,结果表明,多晶体由于晶界的存在会阻止磨屑像单晶体一样沿直线行进,并且晶界会保护内部晶粒使其不易变形。探究了磨削力和磨削温度随磨削参数的变化情况,结果表明,单晶的切向力和法向力都大于多晶,但是多晶的磨削力波动比单晶大,磨削温度也比单晶高。

Voronoi algorithm was used to construct the polycrystalline 3J33 model.Molecular dynamics(MD)was used to simulate the grinding of monocrystalline and polycrystalline 3J33 nanometer.The embeded atomic momentum(EAM)and Morse potential functions were used to calculate the atomic forces inside the workpiece and between the workpiece and the grit.The characteristics of the nanometer grinding process of monocrystalline and polycrystalline in unstable and stable stages were studied.The results show that the presence of polycrystalline grain boundary will prevent the grinding chip from forwarding in straight line like monocrystalline,and the grain boundary will protect the inner grain from easy deformation.The grinding forces and grinding temperature with the change of grinding distance were studied.The results show that the tangential force and normal force of monocrystalline are greater than those of the polycrystalline,but the fluctuation of polycrystalline grinding force is bigger than that of monocrystalline,and the grinding temperature of polycrystalline is also higher than that of monocrystalline.