三维金属切削过程的有限元模拟-机械制造及发自动化专业毕业论文.docx

华北电力人学硕士学位论文摘 华北电力人学硕士学位论文 摘 要 在金属切削加工中，对切削过程的研究有着重要的意义。已有的研究表明，数值方 法是研究切削加工过程的-3中有效手段。为此，本文采用三维热力耦合有限元模拟技术， 对金属切削过程进行了系统的研究。 本文首先系统分析了金属切削过程的有限元建模理论，建立了金属切削三维热力耦 合刚粘塑性有限元模型，确定了材料模型、切屑分离准则、网格划分、接触摩擦模型、 磨损模型和边界条件等。基于DEFORM．3D软件平台，成功地模拟了金属切削加工过程。 揭示了等效应变、温度场、刀具磨损的分布规律。模拟结果表明该模型是可靠的。 研究揭示了主要工艺参数对切屑变形、切削力、切削温度、刀具磨损的影响规律。 通过与理论分析的比较，验证了数值模拟的可行性，为工艺参数优化、切削质量控制及 刀具设计提供了依据。 关键词：切削，三维数值模拟，刚粘塑性有限元，热力耦合 ABSTRACT In the field of metal cutting，it has an important significance to the investigation of the cutting process．The existed researches show that it is effective to investigate cutting process using numerical method。Therefore，in this paper,a systematic investigation on metal cutting process has been carried out using 3D coupled thermal·mechanical FEM numerical simulation． In this paper,the finite element models of metal cutting were first discussed systemically． A 3D fmite element model under coupled thermo—mechanical effects of metal cutting has been developed based on rigid-viscoplastic FEM，and some key technologies have been confirmed， including material model，chip separation criteria，meshing，the contact friction model， abrasion model，contact boundary,etc．Based on the platform of finite element software DEFORM一3D，the processes of metal cutting were simulated successfully．The laws of distribution have been disclosed for equivalent strain field，temperature field and tool wear． The model has been validated by simulation results to be reliable． The influence of main process parameters on chip．distortion，cutting force，cutting temperature and tool wear have been disclosed．By comparing with the theoretical analysis， the feasibility of the numerical simulation was validated，the obtained results may provide a guide to optimizations of process parameters，control of the cutting quality and tool design． KEY WORDS：Machining，Three dimensional numerical simulation，rigid—viscoplastie FEM， thermal—mechanical 华北电力人学硕士学位论文摘 华北电力人学硕士学位论文 摘 要 在金属切削加工中，对切削过程的研究有着重要的意义。已有的研究表明，数值方 法是研究切削加工过程的-3