【作者】 梁磊；

【导师】 郑建明； 李言；

【作者基本信息】 西安理工大学 ， 机械电子工程， 2006， 硕士

【摘要】 金属切削加工是利用刀具和工件相对运动去除工件上多余金属或余量以获得合乎要求的零件的加工方法之一。金属切削过程是一个高度非线性、热力耦合的过程。为了弄清出切削机理,提高加工效率以及对加工过程的参数优化,获得最好的加工效果,国内外都对金属的切削过程进行了广泛的研究。本文通过有限元技术对正交切削过程进行模拟分析,以便为改进切削工艺和加工参数优化提供理论依据。本文根据金属切削的理论,对金属正交切削过程进行了的分析和研究;结合有限元理论和实际金属正交切削的特点,提出了有限元分析模型。针对此模型,应用DEFORM有限元软件,将工件、刀具材料的一些特性参数结合起来,分析和定义了载荷边界条件,对刀具前刀面与切屑之间复杂的摩擦状况,用库仑摩擦定理作一定的简化处理,定义了切屑分离准则和网格重划标准,完成了有限元分析仿真的预处理工作。对正交切削过程中应力、应变的变形特性进行了模拟仿真,得到了加工过程中应力应变规律和不同加工参数对切削力的影响曲线。通过仿真剪切角的形成过程,验证了剪切角理论,得到了剪切角的仿真结果。建立了切削温度仿真模型,通过对切削过程中温度的仿真研究,得到了切削过程中不同加工参数对切削温度的影响曲线。利用CA6150车床进行切削实验,对仿真结果进行了实验验证,证明仿真结果可以反映实际切削加工过程,可为实际加工参数的选择提供依据和参考。更多还原

【Abstract】 The metal machining is a method which removes the unnecessary metal through the relative motion of cutting tool and the work piece for obtaining expectant components .Metal cutting is a complexity process with exceeding non-linear and heat-stress coupled. In order to clarify cutting mechanism as well as to optimize the machining process parameter and obtain the best processing effect, the researches have been carried out extensively on the metal cutting process. The numerical simulation based on the finite element technology is applied to the metal cutting process in this paper, in order to provide the theory basis for the improvement cutting art and the optimization processing parameter.The metal orthogonal cutting process is studied on the base of metal cutting theory. The finite element analysis model is proposed on the foundation of the finite element theory and the actual metal orthogonal cutting characteristic. In view of this model, applying the DEFORM finite element software, combining the work piece with cutting tool material characteristic parameter, the load boundary condition is defined and complex friction condition between cutting tool rake and scrap with the coulomb friction theorem is simplified. The nodes separation the criterion from mesh and remeshing standard are put forward .The pretreatment of simulation work is completed.The chip stress-strain rule and the different processing parameter to the cutting force the influence curve are obtained under the simulation of the chip distortion in the orthogonal cutting process. The angle of shear principle is confirmed, obtained the angle of shear simulation result through the simulation angle of shear forming process.The cutting temperature simulation model is established. The different processing parameter to the cutting temperature influence curve is obtained through the simulation the cutting temperature in metal machining.The cutting experiment is carried out by the CA6150 lathe. The simulation results are proved by theexperimental result. All these imply that simulation machining process is feasible and may provide the reference for the actual processing parameter choice.更多还原