基于刀具变形和工件亚表层质量预测模型的自由曲面超精密铣削加工运动规划

项目名称： 基于刀具变形和工件亚表层质量预测模型的自由曲面超精密铣削加工运动规划

项目编号： No.51475188

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 机械、仪表工业

项目作者： 彭芳瑜

作者单位： 华中科技大学

项目金额： 90万元

中文摘要： 在自由曲面超精密铣削加工过程中，刀具磨损和变形等引起的加工误差对自由曲面加工精度影响非常显著。同时，其亚表面层质量，如残余应力、显微硬度、变质层等，还会显著影响其使用寿命和性能。 本项目在分析刀具磨损、变形以及工件亚表层质量和加工工艺参数之间非线性映射关系的基础上，建立超精密铣削加工过程中刀具磨损、变形和工件表面亚表层质量的数学模型。开展了基于几何以及物理混合约束的自由曲面超精密铣削加工运动轨迹规划研究，对加工工艺参数进行优化，并在刀具运动轨迹中对加工误差进行迭代补偿，以提高自由曲面超精密铣削加工精度，降低表面亚表层损伤。 本项目的研究成果将为光学自由曲面模具超精密铣削加工提供具有自主知识产权的核心理论与关键技术，有助于拓展超精密铣削在复杂光学自由曲面加工领域的应用。

中文关键词： 超精密铣削；自由曲面；刀具变形；工件亚表层质量；运动规划

英文摘要： In the process of ultra-precision milling for free-form surface, machining error caused by wear and deflection of cutting tool has significant effects on machining precision of free-form surface. In the meanwhile, the quality of the subsurface, such as residual stress, microhardness and deterioration layer, will obviously affect its service life and performance. On the basis of analysis of the nonlinear mapping relationship between wear and deflection of cutting tools, quality of subsurface and machining process parameters, the mathematical models of wear and deflection of cutting tools, quality of subsurface are established in the process of the ultra-precision milling. Considering the mixed constraints of geometrical and physical information, a new tool-path planning method is proposed to apply to the ultra-precision milling of free-form surface. Then the processing parameters are optimized, and the machining error is iteratively compensated by tool-path planning. It can improve the machining precision and reduce the subsurface damage in the ultra-precision milling of free-form surface. The achievement will provide the core theories and key technologies with independent intellectual property rights in terms of ultra-precision milling of optical free-form surface mould. It contributes to expand the applications of ultra-precision milling in complex optical free-form surface machining field.

英文关键词： ultra-precision milling;free-form surface;tool deflection;workpiece subsurface quality;tool-path planning