【作者】 李迎春；

【导师】 周晓勤；

【作者基本信息】 吉林大学 ， 机械制造及其自动化， 2014， 博士

【摘要】 有复杂几何特征的自由曲面光学元件在工程光学、生物医学、半导体器件等重要的工业领域有着日益增加的应用需求，这些自由曲面光学元件或制造这些自由曲面光学元件的模具通常所采用的材料主要是一些切削加工性较差的难加工材料。金刚石切削被认为是一种较为高效的获得复杂几何面形的加工方法，然而由于这些难加工材料的较差切削加工性，使得金刚石切削方法主要限于加工有色金属等工件材料。为了扩展金刚石可切削的工件材料范围、提高加工表面质量，论文结合国家自然科学基金项目，针对光学自由曲面三维椭圆振动切削，着重研究刀具路径生成及对加工表面质量的影响。论文主要包括如下五个部分的研究内容。1、介绍了现行的三维椭圆振动驱动方程Ⅰ，但此方程的幅值和初始相位参数与三维椭圆振动轨迹的形状及其在空间中的位置没有直接的依赖关系，需要通过较为复杂的推导以获得它们之间的依赖关系，因此无法研究三维椭圆振动轨迹的形状及其在空间中的位置对加工表面质量的影响。所以本文对三维椭圆振动驱动方程进行了重表示，定义了一种能够表征形状和空间位置的三维椭圆驱动方程Ⅱ，此三维椭圆驱动方程包含七个参数，其中四个参数可以表征三维椭圆的形状，另外三个参数可以表征三维椭圆的空间位置。由于三维椭圆振动驱动方程Ⅰ和三维椭圆振动驱动方程Ⅱ中包含的椭圆参数的个数与意义均不相同，所以本文利用谐波分析方法实现了两类椭圆驱动方程中的参数匹配，为研究三维椭圆形状和空间位置对表面质量的影响奠定了理论基础。2、三维椭圆驱动方程Ⅱ的参数变化对三维椭圆驱动方程Ⅰ的参数是有影响的，所以本文研究了两类三维椭圆驱动方程参数之间影响关系。揭示了三维椭圆驱动方程Ⅱ的平面椭圆振幅比、平面椭圆相位差以及平面椭圆绕y、 z、 x轴旋转角度对三维椭圆驱动方程Ⅰ的y向与x向之间的振幅比ba和相位差y x、z向与y向之间的振幅比cb和相位差z y以及z向与x向之间的振幅比ca和相位差z x的影响规律。3、研究了三维椭圆振动切削光学自由曲面的刀具路径生成算法，综合考虑了刀具几何参数、切削工艺参数、三维椭圆振动、刀具圆弧半径补偿及刀触点与刀位点之间的位置关系等因素，并阐述了如何应用此刀具路径进行切削实验，以复曲面和正弦曲面为例验证了刀具路径算法的有效性。4、针对正弦波面和复曲面，采用所提出的刀具路径算法，进行了加工表面残留形貌的分析。通过加工表面残高形貌的影响分析，揭示了三维椭圆振动参数（振动幅值、相位差等）和切削工艺参数（刀具进给量、刀尖圆弧半径等）对加工表面粗糙度的影响规律，对切削过程中如何选取椭圆振动参数、切削工艺参数进行了定量的分析。5、以三维椭圆的形状参数和空间位置参数作为优化变量，以表面粗糙度值最小作为目标函数，建立了三维椭圆振动参数优化的数学模型，应用遗传算法对三维椭圆振动参数进行了优化，为选择最优的三维椭圆振动参数进行切削实验提供了理论基础。本文的研究为应用三维椭圆振动切削光学自由曲面提供理论基础。更多还原

【Abstract】 There is an increasing use of optical parts on difficult-to-cut materials in a range ofapplication areas, including optical engineering, biomedical and semiconductor products etc.However, most of these optical materials and the mold materials of processing these opticalparts are difficult-to-cut materials, which have poor machinability. Diamond turning hasbeen reviewed as a high efficient method to machine the surfaces with complex shapes,while the diamond turning method is used to fabricate the nonferrous materials for the poormachinability of the difficult-to-cut materials. In order to expand the range of the diamondmachineable materials and improve the surface quality, this paper focuses on the tool pathgeneration and the effects of the parameters to the surface quality of three-dimensionalellipse vibration cutting optical freeform surfaces under the support of National NaturalScience Foundation of China. The followings works are researched in this paper.Firstly, the three-dimensional (3D) ellipse driven equation (EDE) Ⅰ is introduced,which can’t represent the shape and space location of the3D ellipse. So the3D EDE Ⅰcan’t be used to research the influence of the ellipse parameters to the surface quality. The3D EDE Ⅱ is defined which can represent the shape and space location of the3D ellipsein this paper. It includes4shape parameters and3space location parameters. Because theparameters are different between these two ellipse driven equations, harmonic analysis isused to match the ellipse parameters of these two ellipse driven equations. This research canprovide the theory basis for revealing the laws of the ellipse parameters to the surfacequality.Secondly, the changes of the3D EDE Ⅱ parameters will affect the parameters of the3D EDE Ⅰ. So the relationships of the parameters are researched between these two typesof equations. The laws of the changes of3D EDE Ⅱ parameters to the the parameters of3D EDE Ⅰ have been revealed.Thirdly, the algorithm of the tool path generation is proposed, considering the tool geometry parameters, the cutting process parameters,3D ellipse vibration, tool arc radiuscompensation and the position between the cutter-contact point and the cutter-location point.At the same time, how to use the tool path to machine the optical freeform surfaces has beendescribed clearly. The examples of the toric surface and sinusoidal surface are used toverify the tool path.Fourthly, the machined surface residual height topography is analysed according to thetoric surface and sinusoidal surface. The laws of the ellipse parameters, cutting parametersand tool parameters to the surface quality have been revealed. This research can telldesigners how to choose the ellipse parameters, cutting parameters and tool parameters tomachine optical parts.Fifthly, genetic algorithm is proposed to solve the optimum ellipse parameters whichare the shape and position parameters. This research can provide theory basis for thedesigners to use optimum elliptical vibration parameters to machine optical freeformsurfaces of difficult-to-machine materials in the cutting experiments.This research can provide theory basis for three-dimensional ellipse vibration cuttingoptical freeform surfaces.更多还原