陶瓷基复合材料表面的超脉冲激光复合平整加工理论与方法

Ceramic matrix composite, with its excellent thermodynamic performance, has been used as structural materials in hot end components of aeronautics and astronautics. However, the machining precision in Mounting surface of ceramic matrix composite parts assembly, made of hot pressing forming, restricted the aerospace aircraft application in harsh environment condition as well as the improvement of its function and properties. Aim to the theory and technology problem in flattening on surface of ceramic matrix composite with high-quality and efficient, this project provides a new theory and method in laser compound flattening on surface of ceramic matrix composite. This project centers on the scientific issue concerning the flattening-removal mechanism of ceramic matrix composite under combined effect of super-pulsed laser and multiple energy field as well as the surface topography/microstructure evolvement regularity. This project further researches on surface material removal mechanisms, surface morphology and internal microstructure evolvement mechanisms induced by super-pulsed laser and multiple energy field, and thus the realization method in flattening on surface of ceramic matrix composite using super-pulsed laser compound machining. It is expected to achieve the equipment innovation and technology breakthrough in super-pulsed laser compound flattening on surface of ceramic matrix composite. Furthermore, it will break through the key technical barrier in manufacturing in hot end components of aeronautics and astronautics and the research results can provide the processing theory and technology support for the ceramic matrix composite application in core components of aeronautics and astronautics.

陶瓷基复合材料凭借其优异的热力学性能成为航空航天热端功能部件重要的结构材料，然而采用热压成型的陶瓷基复合材料部件装配面的加工精度严重制约其在航空航天飞行器复杂恶劣环境的应用以及功能和性能的提升。本项目针对陶瓷基复合材料表面高效高质平整加工的理论与技术难题，旨在创建超脉冲激光复合平整加工的新理论与新方法。项目围绕基于超脉冲激光复合多能场调控的平整去除机理与表面形貌/微观组织演变规律这一科学问题，研究超脉冲激光复合多能场致材料表面的去除机理、激光复合多能场致加工表面形貌及内部组织的演化机理、陶瓷基复合材料表面的超脉冲激光复合平整加工实现方法，预期实现陶瓷基复合材料表面的超脉冲激光复合平整加工在理论、技术与装备上的创新与突破，研究成果将突破航空航天陶瓷基复合材料热端功能部件制造中最关键的技术瓶颈，为陶瓷基复合材料在航空航天核心部件的实际应用提供加工理论与技术支持。

本项目旨在突破航空发动机陶瓷基复合材料(CMC-SiC复合材料)热端功能部件制造技术瓶颈，在超脉冲激光复合多能场加工陶瓷基复合材料领域取得一系列原创性成果。首先，建立了超脉冲激光电离粒子束动态密度模型实现了等离子体的动态追踪与状态调控，建立了超快激光与CMC-SiC复合材料作用的电子动力学模型，发现了等离子组分和密度的空间分布对CMC-SiC复合材料的作用规律；其次，建立了激光-超声-流场多能场作用下空化气泡演变的仿真模型，发现了水溶液、超声振动作用下飞秒激光加工CMC-SiC复合材料的相变裂纹演变规律及抑制措施，揭示了激光二次自聚焦、激光诱导空泡、溶液表面张力和粘度对CMC-SiC复合材料抛光质量的影响规律，发现了多能场耦合作用下激光参数对复合材料中各组分的去除规律；再次，搭建了双束激光参数动态匹配和脉冲间时序耦合系统，实现了光路系统时间序列高分辨控制（延时精度5fs）与空间高精度耦合（光斑重叠率＞95%），探索了双脉冲激光时序与能量调控对烧蚀效率的影响规律；最后，自主设计并集成超声高频微振、溶液、等离子体在线监测、超脉冲激光、光机电协同控制等模块，研制了超脉冲复合平整加工CMC-SiC复合材料的原型系统，实现了对CMC-SiC复合材料的高品质平整化加工，加工表面无纤维断裂、纤维拔出、孔洞等缺陷，表面粗糙度从原始的Ra3.98μm降低到了Ra0.875μm~Ra0.936μm，平整去除厚度达58.291μm，抛光效率4.89mm^3/min，技术成果具有实际应用价值。通过本项目的研究，在Chemical Engineering Journal、 IEEE Transactions on Industrial Informatics、ACS Applied Materials & Interfaces、Corrosion Science、Optics Express、Applied Physics A等国际高水平学术期刊上发表第一标注论文32篇（其中SCI论文24篇，ESI高被引论文3篇），申请中国国家发明专利7项，其中授权3项，获得软件著作权1项，出版专著1项，制订团体标准1项，研究成果获陕西省技术发明一等奖（2022）、“红光奖”-激光科技创新杰出贡献奖（2022）；培养硕士/博士共17名、博士后3名，项目成员获教育部“青年长江学者”、国家优秀青年科学基金等