基于SPH法的钢轨打磨单颗磨粒磨削仿真

为研究钢轨打磨过程中材料的去除机理，采用光滑粒子流体动力学（SPH）的方法，仿真模拟钢轨打磨过程中单颗磨粒的切削过程，分析单颗磨粒几何形状、切削深度、负前角对打磨磨削过程中切削力、切削力比的变化规律及工件材料应力、变形情况的影响。结果表明:由于单颗磨粒的推挤作用，工件材料流动后形成毛刺和磨屑，而棱锥形磨粒可以获得较好的磨削加工表面；切削力随磨粒切削深度的增加而增大；磨粒负前角增大时，切削力和切削力比都随之增大，且负前角越大磨屑呈越明显的锯齿状。 

Simulation of single grain grinding in rail grinding based on SPH method

In order to study the material removal mechanism of rail grinding,smoothed particle hydrodynamics(SPH)method is used to simulate the single grain cutting process of rail grinding.In this work,single grains with different geometries,cutting depths and negative rake angles are assumed to cut workpieces.Changes of cutting force,cutting force ratio,stress and deformation of the workpiece are analyzed.Resultsshow that material flow generates burr and chip due to grain pressing,and that the machined surface is superior when the grain is pyramid.In addition,the cutting force increases with increase of cutting depth.Bigger negative rake angle leads to higher cutting force and cutting force ratio,as well as more obvious sawtooth shapd chips.