【作者】 王伟；

【导师】 王霄；

【作者基本信息】 江苏大学 ， 机械工程（专业学位）， 2017， 硕士

【摘要】 碳纤维复合材料(Carbon Fiber Reinforced Plastics,简称CFRP)相较于传统的钢铁来说密度小、加上CFRP的比模量、比强度高、耐腐蚀性好、抗疲劳能力突出、减振效果以及可设计性优于传统材料,在国防领域、航空航天领域、交通、医疗、军事等领域的应用前景广阔。但是,由于CFRP加工知识的缺乏,导致市面上的CFRP制品的品种少、质量也不高,因此,采用新的手段来研究CFRP的加工方法,丰富CFRP的相关加工知识是当前切削加工的一个研究热点,对于能否成功在科研、生产中大范围应用CFRP具有战略意义。本文以CFRP为研究的对象,以CFRP相关切削机理和有限元分析理论为基础,采用工艺仿真软件Deform创建CFRP的3D铣削模型,采用单因素法模拟了CFRP的铣削情况,分析了铣削力、表面应力、铣削温度、CFRP的表面加工质量以及刀具的磨损情况;采用Isight软件对CFRP进行基于多目标的参数优化分析;最后对CFRP进行与模拟方案以及优化方案一致的铣削试验,与模拟进行对比,证明了模拟和优化的可靠性,说明了采用数值模拟方法来研究CFRP的铣削加工是完全可行的。本文的主要研究内容和成果如下:1.探讨了CFRP的材料特性、切削机理和加工缺陷,研究了影响切削力的因素,研究了CFRP有限元分析的建模理论以及有限元建模的关键技术。为具体采用有限元分析软件求解CFRP的铣削情况奠定了理论基础。2.通过工艺系统仿真软件Deform建立了CFRP材料本构模型以及3D铣削有限元模型,模拟了碳纤维复合材料的三维动态铣削过程;采用单因素法分别改变主轴转速n、进给量f、背吃刀量pa、径向切深ea、刀具材料,分析了各因素对CFRP铣削过程中X、Y、Z三个方向的铣削力、铣削温度、工件表面应力、刀具磨损、工件表面的加工质量的影响,得到结论:当采用PCD刀具时、在高的主轴转速、较低进给量、较高的背吃刀量以及较大的径向切深时,得到的铣削力、铣削温度以及工件的表面应力较低,并且刀具的磨损较轻,工件的表面加工质量良好同时加工效率有一定的提高。3.采用多目标优化软件Isight进行参数优化,以主轴转速n、进给量f、背吃刀量pa、径向切深ea为初始设计变量,采用正交试验设计法进行试验设计并采集足够的样本点,之后采用响应面法建立近似模型并对响应面模型进行交互式影响分析,分析设计变量对响应模型的主效应,最后对响应面模型进行精度检测以及误差分析,显示检测合格。用AMGA存档微遗传算法对设计变量进行多目标优化分析,找到最优解,优化后,铣削力yF、zF和铣削温度T有所下降,实现了优化的目的。4.在数控加工中心上进行铣削试验,试验的方案与模拟方案和优化方案相同。通过VHX-1000C型超景深显微镜对CFRP试样进行表面形貌的观察,将铣削试验的观测结果与模拟结果进行对比分析。结果显示,铣削试验的观测结果同有限元模拟结果的吻合度较高。采用优化方案进行铣削试验,观察表面形貌,将铣削试验的观测结果与有限元模拟的结果进行对比分析。结果显示,采用优化方案进行CFRP铣削试验得到的表面质量有一定的提高。最终得到结论,CFRP铣削有限元模型具有较高的可信度,并且参数优化的结果可行,说明通过有限元模拟的方法进行CFRP铣削模拟是完全可行的,对生产实践具有一定的参考意义。更多还原

【Abstract】 The density of CFRP is smaller than steel,and it has high specific modulus,high specific strength,good corrosion resistance,anti-fatigue ability,vibration reduction and design ability is better than traditional materials and can be widely applied in aerospace,military,medical and other fields of automobile.However,due to the lack of CFRP processing knowledge,resulting in fewer varieties of CFRP products on the market and the quality is not well.So,studying the processing methods of CFRP by taking of new methods,and enriching the related processing knowledge of CFRP are of strategic significance to apply CFRP to a wide range of scientific research and production.In this dissertation,carbon fiber composite material is studied and based on the CFRP related cutting mechanism and finite element analysis theory,build the 3D milling model by using the process simulation software Deform.Using single factor method to simulate the CFRP milling condition under different milling parameters and analysis of the milling force,milling temperature,surface stress,tool wear and the machining quality.Using multi objective optimization software Isight to make the multi-objective optimization.Finally,the CFRP milling experiments are carried out on the basis of the simulation parameters and optimization parameters and compared with the simulation results,proved the reliability of simulation and optimization.It is proved that the numerical simulation method is feasible to study the milling of materials.The main research contents and results are as follows.1.Discussing the material properties,cutting mechanism and machining defects of CFRP.Studying the factors that affect the cutting force and the modeling theory of finite element analysis and the key technology of finite element modeling about CFRP and laying the theoretical foundation for finite element analysis software.2.To establish the constitutive model of CFRP and the three-dimensional finite element milling model,and the dynamic milling process is simulated by Deform.Changing the spindle speed n,feed rate f and cutting depth pa,the radial cutting depth ea and cutting tool material by using the single factor method.The effects of various factors on milling force in three directions of X,Y and Z,milling temperature,surface stress,tool wear and machining quality were analyzed and get the results: When using PCD tool,high speed,low feed,higher cutting depth and larger radial cutting depth,the milling force,milling temperature,surface stress is low,and can get small tools wear,good machining quality and high efficiency.3.Using multi objective optimization software Isight to optimize the parameters,The original design variables are spindle speed n,feed rate f and cutting depth pa,the radial cutting depth ea.Using the orthogonal design to design the experiment and collecting enough samples.Using the response surface method to establish the approximate model and the interaction analysis is performed on the response surface model.The main effect of design variables on response model is analyzed.Finally,the accuracy analysis and error analysis of response surface model show qualified.Doing multi objective optimization of design variables by using AMGA archive genetic algorithm and find the perfect result and the milling force yF,zF and milling temperature T decreased,and the purpose of optimization was achieved.4.Doing the same conditions milling experiments on the machining center,Observe surface morphology of samples by using VHC-1000 C type super depth of field microscope and the results of finite element simulation are compared with milling experiment.The results show that the agreement between the observed results and the finite element simulation results is higher.The milling experiment is carried out according to the optimization scheme and observe the surface morphology,compare the results of finite element simulation with milling experiment and analyzed and the result show that the surface quality of CFRP is improved by using the optimized scheme.Finally get the results: The milling finite element model of CFRP has high reliability and the result of parameter optimization is feasible.It is proved that the milling finite element simulation method is feasible and it has certain reference significance to the production practice.更多还原