抗疲劳表面状态及其多工艺复合控制域反演方法

Domestically-made aero engine has short lifetime, poor reliability and non-standard property, the reason is the weak foundation of material and manufacturing. Moreover, controlling of surface integrity is the weakest and shortest ‘short board’ among the foundation of domestic manufacturing technology. This project takes the GH4169 superalloy key components of aero-engine as the research object. Aiming at precision milling, polishing, and ultrasonic impact strengthening processes, the inverse method of anti-fatigue surface state and its controlling area of integration manufacturing processes are studied systematically. Based on the 3-D distribution characterization of surface state, the macro influence model between surface state and fatigue property is established. The reconstruction rule of surface state during integration manufacturing processes is revealed, and the influence rule of surface state on fatigue life is clarified. A new method for designing the anti-fatigue surface state characteristic is established, in which the fatigue property is taken into account. Furthermore, based on the surface damage and surface integrity, a method for controlling process area during integration manufacturing processes is proposed. The research results can provide the basic model and process method for achieving long life and high reliability manufacturing of aero engine key components.

国产航空发动机寿命短、可靠性差、性能不达标，根源是材料与制造基础薄弱，而表面完整性控制是国内制造工艺基础中最薄弱、最短的一块“短板”。本项目以发动机GH4169高温合金关键构件为对象，针对精密铣削、抛光和超声冲击强化等典型制造工艺，开展抗疲劳表面状态及其多工艺复合控制域反演方法研究，基于表面状态三维分布表征，建立表面状态与疲劳性能的宏观影响模型，揭示表面状态多工艺复合重构规律，阐明表面状态对疲劳性能的影响机制，建立基于疲劳性能的表面状态特征梯度分布反演设计方法，及基于表面损伤度和完整性的多工艺复合控制域反演方法，为实现航空发动机关键构件长寿命高可靠制造提供基础模型和工艺方法支撑。

航空发动机关键构件的抗疲劳制造涉及铣削、光整、强化等多种工艺的复合与集成应用。与单工艺相比，多工艺复合加工的表面状态具有可设计性。本项目以发动机GH4169高温合金和TC11钛合金精密铣削和表层强化为研究对象，通过理论建模、工艺实验、测试分析、疲劳试验等，开展抗疲劳表面状态及其多工艺复合控制域反演方法研究。具体内容包括：表面状态与疲劳性能的宏观影响模型、表面状态多工艺复合重构及其对疲劳寿命的影响、基于疲劳性能的表面状态特征梯度分布反演设计、基于表面损伤度和完整性的多工艺复合控制域反演。本项目旨在探索多工艺复合加工下抗疲劳表面状态的重构规律、梯度分布设计和工艺参数优化的科学问题，提出并建立基于疲劳性能的表面状态及其工艺控制域反求设计方法，为实现航空发动机关键构件长寿命高可靠制造提供基础模型与工艺方法支撑。