【作者】 柯烈强；

【导师】 王立涛；

【作者基本信息】 安徽工程大学 ， 材料科学与工程， 2010， 硕士

【摘要】 整体结构件数控加工变形是航空制造业面临的最突问题之一,严重地阻碍了航空制造业的发展进程。研究影响整体结构件加工变形因素及减小或抑制零件加工变形的工艺,对航空整体结构件数控加工变形的预测及控制具有十分重要的价值和意义。全文共分六章,各章内容简述如下：第一章阐述了论文研究的背景和意义,总结了航空整体结构件数控加工变形的国内外研究现状,提出了本论文的研究内容和总体框架。第二、三章在阐述航空整体结构件加工变形的相关理论基础上,通过理论分析、有限元计算及实验研究相结合的方法。从三维切削机理,加工变形特征及整体结构件数值模拟关键技术入手,对航空整体结构件的铣削加工变形进行了深入的研究。建立了适合航空框类整体结构件铣削加工变形的有限元模型,并深入研究了所需的建模关键技术,主要包括模型简化研究、材料去除方法、切削层简化及切削载荷施加。第四章采用有限元模拟与试验研究相结合的方法,针对航空多框整体结构件的铣削加工变形机理、预测方法以及变化规律开展了深入的研究,为该类结构件加工变形的控制奠定了基础。利用三维弹塑性有限元技术分析了走刀路径和加工顺序对铣削加工残余应力分布和变形的影响,得到了四种典型的走刀路径以及框铣顺序对加工变形的影响趋势。第五章结合实际小尺寸结构件的高速铣削加工试验,采用三坐标测量仪测量工件的加工变形,通过加工变形模拟结果与试验结果的对比分析,验证了所建立的加工变形有限元分析模型的有效性。第六章对本论文的研究内容进行了总结,并对进一步研究工作进行了展望。更多还原

【Abstract】 The machining distortion of monolithic components is one of the most striking problems in aviation manufacturing industry and hinders the development of the aeronautical industry seriously. It has important value to investigate the effect factors of machining distortion and methods for reducing or avoiding distortion.Six chapters are included in this dissertation, and the main work is as follows.In chapter 1, the background and significance of this research is introduced firstly. Then, the state of the art in the research of machining distortion of the monolithic component is summarized. Finally, the main contents and frame structure of this dissertation are shown.In chapter 2 and 3, based on the theory of cutting deformation of Aerospace monolithic components, from three dimensional cutting principles, the characteristics of machining distortion,and the key modeling techniques of monolithic components for the simulation, a method combining theoretical analysis with Finite element calculation and experiment is adopted in this dissertation to study the distortion prediction. The key modeling techniques of the machining distortion simulation for the milling process of monolithic components have been investigated, which include the simplification of geometrical model, simplification of cutting layer and the application of cutting loads.In chapter 4, by using finite element simulation and experiments, a deep study is carried out on the mechanism, the prediction method and the variation tendency of the milling distortion. The work in this dissertation can provide a basis for the distortion control of the monolithic multi-frame components. The effect of tool path and machining sequence on residual stresses as well as machining distortion are analyzed by using three-dimensional elastic-plastic FEM(Finite Element Method). The distortion variation tendency on milling under four typical tool paths, machining sequence is obtained respectively.In chapter 5, small dimension parts was machined and its deformation was measured on a coordinate measuring machine to comparing the simulation results and the real measurement in the distortion, the proposed model is proved to be effective.In chapter 6, systematical summary for the whole work in this dissertation is given, and future work is discussed. Author:Ke lieqiang(Material Science) Supervised by:Prof.Wang litao更多还原