舰载机起落架激光辅助铣削的多热场切削机理与高品质工艺优化研究

Aimed at laser assisted milling of carrier aircraft landing gear, the internal relationship between milling mechanism and process quality is deeply studied, new process optimization theory and method are established. This is able to meet the urgent demand of high quality machining for carrier aircraft landing gear parts. Carrier aircraft landing gear is chosen as the research objective of this project, multi-thermal field cutting mechanism during laser assisted milling is researched. Workpiece temperature distribution and cutting force prediction models considering the interactions between laser and cutting heat sources are presented. Considering the effect of process parameters such as laser capacity, frequency, spot size, and cutting depth, radial depth, feed rate etc., the models of tool life, surface residual stress, micro crack and deterioration layer from laser assisted milling are presented. Based on the models and experimental data of tool life, surface residual stress, micro crack and deterioration layer from laser assisted milling, the process parameters are optimized by establishing reinforcement learning model. Then, the digital simulation and experiment platforms for process parameters optimization based on reinforcement learning model and stability active control based on electromagnetic constraint module are established. The software module for process parameters optimization, multi-axis motion matching and stability active control during laser assisted milling is developed. Finally, the goal of high quality machining for carrier aircraft landing gear can be achieved based on the above theory and practical researches. This achievement will provide the core theories and key technologies with independent intellectual property rights in terms of laser assisted milling process quality optimization for carrier aircraft landing gear. It contributes to expand the applications of laser assisted milling in the machining field of large complex shaft parts.

针对激光辅助铣削加工舰载机起落架，深入研究切削机理与工艺品质之间的内在关系，建立新的工艺优化理论和方法，可满足舰载机起落架难加工零件对高品质加工的迫切需求。本项目以舰载机起落架为研究对象，开展激光辅助铣削加工多热场作用下铣削力热研究，考虑激光功率、频率、光斑大小与铣削轴向切深、径向切宽、进给速度等工艺参数对刀具寿命和加工表面质量的影响，建立考虑力热效应的刀具磨损、加工表面微裂纹、残余应力及变质层等模型。以刀具磨损、残余应力等模型和实验数据为基础，采用强化学习的方法优化工艺参数。建立工艺优化数字仿真与实验平台，开发工艺参数优化、激光辅助铣削多轴运动匹配和加工稳定性主动控制的软件模块。通过上述理论与实践研究，实现舰载机起落架的高品质加工。本项目的研究成果将为舰载机起落架激光辅助铣削加工工艺品质优化提供具有自主知识产权的核心理论与关键技术，有助于拓展激光辅助铣削在大型复杂轴类零件加工领域的应用。

超高强度钢AerMet100属于典型的难加工材料，具备优异的综合力学性能，是制造舰载机起落架、火箭壳体等重要结构件的先进材料。激光辅助铣削是应用于加工难加工材料的一种复合加工技术，通过激光束的热效应使待去除材料受热软化，可达到改善材料切削性能的目的。.为提高激光辅助铣削的加工效率和加工品质，本项目围绕激光辅助铣削超高强度钢AerMet100切削机理、表面完整性（残余应力和白层）预测、工艺参数优化和颤振主动控制开展研究。主要研究内容和成果包括：1. 激光辅助铣削多热场作用下铣削力热建模与分析。建立考虑材料软化的激光辅助铣削切削力和工件温度场预测模型，分析激光加热和塑性变形综合作用下的工件亚表层剪切流动应力的变化规律和剪切面温升的演变规律。研究表明，激光预热材料软化，对降低切削力效果显著。2. 激光辅助铣削表面完整性分析与工艺参数优化。建立激光辅助铣削残余应力解析预测模型和考虑相变的工件亚表层白层厚度解析预测模型，分析工件表面残余应力和白层分布规律；白层厚度混合驱动模型和遗传算法相结合，实现激光辅助铣削工艺参数优化。研究结果表明，选择合理的激光功率和加工参数，可以有效控制残余压应力的分布，减少白层的形成。3. 激光辅助铣削动态特性分析与颤振主动控制。开展激光辅助铣削动态特性和加工稳定性分析；设计基于压电作动器的颤振主动控制装置，开发基于C#的颤振主动控制软件平台。.通过本项目的实施，建立了激光辅助铣削A100钢表面完整性数字仿真与实验平台，实现了工艺参数优化，开发了切削力和加工稳定性仿真模块，为工艺人员编制高效高品质工艺提供了有力的工具。到项目结题为止，发表论文10篇，SCI 刊源 6篇，EI刊源 10篇。授权发明专利3项，受理发明专利1项。培养博士研究生3名，培养硕士研究生4名，参加国内外学术交流6人次。