淬硬45钢斜角切削锯齿形切屑的有限元模拟

Finite Element Simulation of Serrated Chip in Inclined Cutting of Hardened 45 Steel

目前大多数对高速切削锯齿形切屑的仿真模拟都是针对二维直角切削,三维仿真模拟极少。实际切削加工是一个三维变形过程,为了更准确地揭示高速切削机理,亟需开展三维切削加工过程中锯齿形切屑的仿真研究。本文针对淬硬45钢(45HRC)斜角高速切削过程中锯齿形切屑的三维有限元建模及分析,基于ABAQUS通用有限元软件,采用Johnson-Cook材料模型和失效应变分离准则,模拟淬硬45钢(45HRC)斜角高速切削过程中锯齿形切屑的形成过程,并对不同刀具前角和切削厚度下的切屑锯齿化程度、流屑角和宽度变形系数进行分析。结果表明:随着刀具前角的减小和切削厚度的增大,切屑的锯齿化程度越来越明显;切屑的流屑角基本不受刀具前角的影响,近似等于刃倾角,但随着切削厚度的增大而逐渐增大;宽度变形系数随刀具前角的减小和切削厚度的增大而增大。

The research on the simulation of high speed cutting for serrated chip is usually based on 2 D modeling,and the 3 D simulation is rare. Because the cutting process is a 3 D deformation of work-piece,it＇s badly in need of the research on 3 D finite element simulation of cutting process to further reveal the mechanism of high speed cutting. The 3 D simulation inclined high speed cutting of hardened 45 steel（ 45 HRC） is carried out based on ABAQUS. The forming process of serrated chip is simulated by adopting the Johnson-Cook material modeling and separation criterion of failure strain. The change of chip morphology,chip flow angle and deformation coefficient of width under different rake angle and cutting depth are analyzed. The results show that the segment degree of chip becomes larger with the decrease of rake angle and increase of cutting depth. The chip flow angle is not affected by rake angle and its value is approximately equal to inclination angle,but it increases with the increase of cutting depth. The deformation coefficient of width increases with the decrease of rake angle and the increase of cutting depth.