• CN:11-2187/TH
  • ISSN:0577-6686

›› 2012, Vol. 48 ›› Issue (11): 172-182.

• 论文 • 上一篇    下一篇

基于数值仿真技术的单颗磨粒切削机理

言兰;姜峰;融亦鸣   

  1. 清华大学摩擦学国家重点实验室;清华大学精密仪器与机械学系
  • 发布日期:2012-06-05

Grinding Mechanism Based on Single Grain Cutting Simulation

YAN Lan;JIANG Feng;RONG Yiming   

  1. The State Key Laboratory of Tribology, Tsinghua University Department of Precision Instruments and Mechanology, Tsinghua University
  • Published:2012-06-05

摘要: 磨削过程是磨具表面大量形状各异的磨粒参与的多刃切削过程。单颗磨粒切削研究是认识复杂磨削作用的重要手段,但是单颗磨粒切削试验的实施和物理量的测量存在一定的难度。针对这一问题,分别建立单颗磨粒切削的物理力学模型和数值仿真模型,利用不同载荷下的划痕试验验证这两个模型的准确性。利用数值仿真技术研究不同工艺参数下的单颗磨粒切削过程,仿真单颗磨粒的耕犁和切削过程,得到不同切削速度下耕犁向切削行为转变的临界切削深度;当切削深度增加到某一个切削深度时,仿真得到的径向和切向切削力均有突然增大的趋势,同时发现低速时切削力增大的程度明显高于较高速度时切削力的增大程度;仿真得到的最高切削温度随切削深度的增加,呈现先增大后减小再增大的特点,且第一个最高切削温度峰值出现在临界切削深度附近,但是随着切削速度的降低,这个现象明显减弱,当切削速度小于600 m/min时,这个现象基本不存在;仿真得到的材料去除率随着切削深度的增加而显著增大,而且切削速度越大,材料去除率越大。

关键词: 材料去除率, 单颗磨粒切削, 临界切削深度, 切削力比, 切削温度, 数值仿真

Abstract: Grinding process can be considered as micro-cutting processes with irregular abrasive grits on the surface of grinding wheel. The study of the grit-workpiece interaction through single grit cutting is an important contribution to the explanation of the physical processes that occur during grinding. In this study, the mechanical and numerical simulation model of single grit cutting is built. The scratch tests with different load are performed to validate the mechanical and numerical simulation model. Single grit cutting with different process parameters (depth of cut, cutting speed) are modeled by finite element method (FEM) software AdvantEdge. The plowing and cutting processes during single grit cutting are simulated and the critical depth of cut from plowing to cutting is investigated. The simulated tangential and radial cutting forces increase sharply due to the pile-up of workpiece material in the front of single grit when the depth of cut reaches to some value. And the increase extent of cutting forces at low cutting speed is larger than that at high cutting speed. The simulated highest cutting temperature increase first, and then decrease, finally increase again with the increase of depth of cut. And the peak of simulated highest cutting temperature occurs near the critical depth of cut. Follow the decrease of cutting speed, this trend of highest cutting temperature falls down. When the cutting speed is lower than 600 m/min, this trend of highest cutting temperature does not exist. The simulated material removal rate increases with the increase of cutting speed and depth of cut.

Key words: Material removal rate, Critical depth of cut, Cutting temperature, Numerical simulation, Ratio of cutting force, Single grit cutting

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