718镍基合金切削加工过程刀具磨损影响研究

Research on the Influence of Tool Wear in the Process of Machining IN718 Alloy

为分析不同的刀具磨损形式和磨损量对于718镍基合金切削过程和切削结果的影响,基于有限元工具和正交模型对刀具在刀尖圆磨损、后刀面磨损以及月牙洼磨损3种不同磨损形式和不同磨损量条件下对718镍基合金的切削过程进行了相应的仿真。通过建立多个路径对切削过程温度分布和加工后的表面残余应力分布进行提取、求平均值。结果表明,不管何种形式的刀具磨损,都会对切削结果产生明显的影响,随着刀具磨损量的增大,切削力和切削温度都会呈现增大趋势,同时表面残余应力也基本上呈现不断恶化的趋势,不过前期切削温度未能使得材料产生更多的热塑性变形时,切削力占主导作用,此时残余应力的变化呈现相应的反常现象。

In order to analyze the influence of different tool wear forms and tool wear amounts on the cutting process and cutting results,this paper simulates the cutting process of 718 nickel base alloy under three different wear forms and different wear amounts of tool tip circular radius wear,flank wear and crescent depression wear based on finite element tools and orthogonal models,and extracts the distribution of temperature and residual stress by establishing multiple paths Average.The results show that no matter what form of tool wear,it will affect the cutting results.With the increase of tool wear,the cutting force and cutting temperature will increase.At the same time,the residual stress on the cutting surface will basically deteriorate.However,when the cutting temperature in the early stage fails to make the material produce more thermoplastic deformation,the cutting force plays a leading role,at this time,the change of residual stress presents a corresponding abnormal phenomenon.