二维硬态切削过程的有限元仿真毕业设计

I二维硬态切削过程的有限元仿真摘要本文提供了一个用聚晶立方氮化硼刀具（PCBN）切削淬硬钢的有限元分析模型。该模型基于自适应网格技术和大变形技术，从而解决了在切屑变形过程中由于网格变形过大出现的网格畸变问题。在模拟切屑形成的过程中，使用了纯粹的变形技术来弥补了基于切屑分离准则的传统有限元模型的不足。这种方法不仅消除了切屑分离准则和预先定义分离线的需要，同时获得了一个更加真实和合理的切屑成形过程。本文用商业有限元软件ABAQUS/Explicit模拟不同刀具几何参数对切削力的影响，建立了直角切削时平面应变条件下刀具切削过程的仿真模型，并对不同切削几何参数（倒棱角度、切削速度）的有限元模型进行了计算分析和比较，并通过进行正交高速切削实验与仿真结果进行对比，得出了较为合理的硬态切削过程的刀具几何参数，这对实际切削过程的刀具优化设计和降低成本有着重要的指导意义。关键词切削仿真；ABAQUS/Explicit软件；自适应网格技术；二维直角切削II2DCuttingProcessofProcessingandFEMAbstractThispaperpresentsaFEMsimulationmodelfortheanalysisofcuttinghardenedsteelsusingPolycrystallineCubicBoronNitride(PCBN)tool.Themodelisbuiltonanadaptivemeshingapproachanddeformationtechniquewhichsolvestheexcessivemeshdistortionproblemduetolargedeformationexistinginthechipformationprocessofcutting.Inmodelingthechipformation,apuredeformationtechniqueisemployedtoaddressthedeficiencyoftheconventionalFEMmodelbuiltbasedonchipseparationcriterion.Thismethodnotonlyeliminatestheneedoftheuseofthechipseprationcriterionandapre-definedseparatingline,butalsoachievesamorerealisticandreasonablechipformatinprocess.Inthispaperthedifferenttoolgeometricalparameters’effectuponcuttingforcesissimulatedusingcommercialFEMcodeABAQUS/Explicit.Itestablishestheemulationoftoolcuttingprocessin2-Dorthogonalcuttingandplanestraincondition,calculatestheanalyticalmodelsandcomparestheresults,achievesaconsiderablereasonablegeometricalparametersandmorphologicalfeaturesofchipformationduringhardenedsteelcuttingprocess,whichagreeswellwiththepreviousexperiments.Thishasainstructionalsignificanceintheoptimizationoftooledgedesignandhelpscuttingthecost.KeywordsCuttingsimulation;ABAQUS/Explicit;Adaptivemeshingtechnique;2-DorthogonalcuttingIII目录摘要................................................................................................................IAbstract...............................................................................................................II第1章绪论........................................................................................................11.1课题背景...................................................................................................11.1.1课题来源............................................................................................11.1.2课题的研究的背景和意义................................................................11.1.3课题的总体内容................................................................................11.2超硬刀具材料发展状况...........................................................................21.2.1概述....................................................................................................21.2.2超硬刀具材料发展概况....................................................................21.2.3PCBN刀具的性能及应用.................................................................31.3有限元仿真技术在切削加工中应用.......................................................61.4有限元仿真技术发展状况及前景...........................................................81.4.1ABAQUS.............................................................................................81.4.2几种有限元软件的发展和比较......................................................111.4.3国内外有限元软件的发展与现状..................................................121.5本章小结.................................................................................................13第2章有限元方法简介..................................................................................142.1有限元法分析问题概述.........................................................................142.2平面问题的有限元法.............................................................................162.3ABAQUS/Explicit分析的基本原理.......................................................162.3.1切屑成形仿真..................................................................................162.3.2稳定时间限定值..............................................................................172.3.3接触和摩擦分析..............................................................................172.3.4自适应网格技术..............................................................................182.4本章小结.................................................................................................20第3章ABAQUS的仿真建模........................................................................213.1金属切削过程描述.................................................................................213.2ABAQUS仿真模型的建立.....................................................................213.2.1总体模型..........................................................................................213.2.2材料特性..........................................................................................233.2.3边界条件..........................................................................................233.2.4划分网格..........................................................................................233.2.5提交作业..........................................................................................243.3模型子程序.............................................................................................24IV3.4本章小结.....