【作者】 李博；

【导师】 杨将新； 曹衍龙；

【作者基本信息】 浙江大学 ， 机械制造及其自动化， 2015， 博士

【摘要】 本文结合国家重点基础研究发展计划项目“复杂空气分离类成套装备超大型化与低能耗化的关键科学问题”课题“关键部件高强度大构件保质制造技术”(编号：2011CB706505)和国家自然科学基金项目“基于功能-结构并行分解的公差设计理论与方法”(51275464),开展了零件表面的多尺度建模、铣削过程的几何与物理建模、铣削表面形貌的多尺度仿真、基于离散模态系数的铣削表面形貌表征等方面的研究。第1章：综述了零件表面形貌多尺度表征、加工过程建模、铣削表面形貌仿真的研究现状,分析了课题的研究背景和意义,给出了本课题的研究内容和总体框架。第2章：构建了零件表面多尺度误差的表征数学模型；提出了基于改进离散模态分解法(IDMD)的误差表面多尺度建模方法,即通过理想表面的多尺度网格划分、单位化幅值场向量的生成、几何误差系数的生成、尺寸误差系数的生成、不同尺度误差的融合,实现零件误差表面的多尺度建模,同时达到计算时间与精度的平衡。第3章：不同公差原则下,零件表面形貌的多尺度表征模型中各误差系数将大为不同。针对上述问题,本章提出了各公差原则下零件表面模型几何误差与尺寸误差系数的生成方法,实现了零件公差信息与几何模型的统一。第4章：通过研究考虑定位面几何误差影响条件下的定位误差计算方法,分析机床几何误差、主轴误差、工艺参数引起的误差等多源误差对零件精度的耦合机理,提出了多源误差耦合作用下的刀具-零件接触准则,构建了加工过程的几何及物理模型；基于球头铣刀的准静态及动力学结构模型,利用刀具的准静态变形与动态位移响应修正零件加工过程几何模型,实现对铣削表面形貌的多尺度仿真；最后,通过实验验证了本章所提出的方法。第5章：通过仿真分析不同切削条件下的铣削表面形貌,揭示了不同切削参数对铣削表面粗糙度Ra的影响规律；提出了一种基于离散模态系数的铣削表面形貌的表征方法,该方法能够反映刀具残留轮廓的不规则程度,同时能够更加直观表征切削参数与零件表面形貌的关系。第6章：基于MATLAB开发了球头刀5轴铣削表面形貌多尺度预测与分析系统;以MIKRON UCP 600五轴铣床为例对本文所涉及的机床几何误差、切削力系数、刀具的振动模态参数进行了实验测量。第7章：总结了本文的主要研究内容和创新点,对今后的研究工作进行了展望。更多还原

【Abstract】 Supported by the National Basic Research Program of P. R. China "Research on Key Scientific Issues of Super Large and Low Power Consumption Complex Air Separation Equipment" (973 Program, No.2011CB706505), and the National Science Foundation of China ’Theory and Method for Tolerance Design Based on the Parallel Decomposition of Function-Structure" (51275464). The thesis proposes a multi-scale modeling method for the rough workpiece, constructs the geometrical and physical model of the milling process, develops a multi-scale simulation method for the milling surface topography, and presents a modal factors based characterization method for roughness topography of the milling surface.In chapter 1:The history and latest progress of researches on the multi-scale characterization methods for the surface topography, modeling methods for the multi-source errors in the machining process and technologies for the prediction of the milling surface topography are reviewed. The research backgrounds and significances of the thesis are analyzed, and the research contents and general framework are presented.In chapter 2:Proposes a multi-scale characterization method for the workpiece surface; developed a new multi-scale modeling method for the workpiece surface based on the Improved Discrete Modal Decomposition method. By meshing the surface into multi-scale grids, generating the normalized modal vectors, generating the geometrical error factors, generating the dimensional error factors, mixing each scale of deviations, the multi-scale geometrical model of the workpiece is constructed, and the calculating time and precision are balanced.In chapter 3:With different tolerancing principles, the deviation factors of the multi-scale characterization model of the workpiece could be quite different. To solve this problem, with considering the tolerancing principles, generating methods for the geometrical and dimensional deviation factors of the workpiece are propoed in this chapter. Based on those methods the tolerance information and the geometrical model of the workpiece are unified.In chapter 4:By investigating the calculating method for the locating errors with considering the geometrical errors of the datums, analyzing the effects of the geometrical errors of the machine tool, spindle errors, and the errors caused by the cutting parameters on the precision of the finished workpiece, the cutting tool-workpiece engagement boundries are proposed with considering the effects multi-source errors, and the geometrical and physical model of the milling process are developed. Based on the static and dynamic model of the cutting tool, the geometrical model of the milling surface is further modified by the static parts and dynamic parts of the tool deflection. And in result, the multi-scale geometrical features of the milling surface are presented. At the end of this chapter, experiments are carried out to demonstrate the proposed methods.In chapter 5:By simulating the surface topography under different cutting parameters, the relationships between cutting parameters and the roughness value Ra are revealed. And to further describe the surface in detail, this chapter developed a modal factors based characterization method for surface topography of the milling surface, which not only can be used to represent the irregularity of the surface, but also reflect the effects of the cutting parameters on the milling surface.In chapter 6:A software system for multi-scale simulation and analysis of the 5-axis ball-end milling surface is developed based on MATLAB. Measurements about the geometrical errors of the mechine tool, cutting force coefficients and the modal parameters of the cutting tool are conducted based on a MIKRON UCP 600 5-axis ball-end mill.In chapter 7:The research contents and innovations of the thesis are summarized and the future prospects of related research topics are prospected.更多还原