基于单颗磨粒切削的钛合金磨削过程仿真研究

Simulation of single grain grinding TC4 alloy

采用有限元分析软件DEFORM的Johnson Cook材料模型,模拟了润滑涂层单颗磨粒磨削TC4合金的加工过程,对磨屑形成过程中磨削区温度、磨削力和切削变形区内应力的变化情况进行了有限元分析。结果表明:切削高温和高内应力主要集中在剪切变形区的刀尖位置;随着一个锯齿状磨屑节块的生长,温度降低、内应力减小。磨削力和磨削温度随磨屑的形成过程呈规律性变化:随着磨削进行,磨削力逐渐增大,磨削温度也相应升高;在锯齿状切屑完整形成时,磨削力最小、磨削温度最低。

Johnson Cook material model and fracture criterion of commercial finite element software DEFORM were used to simulate grinding TC4 alloy with coated wheel.The chip formation mechanism was discussed and the effects of grinding parameters on grinding force and grinding temperature were investigated.The results showed that cutting deformation was enforced by abrasive rake angle,resulting in shear slip instability on the concentrated shear plastic zone and forming jagged chip.In addition,grinding temperature,grinding force and residual stress changed periodorically along with chip formation during single abrasive grinding.