铜基复合材料高速切削过程摩擦效应研究

高速切削是实现广泛应用的高性能铜基复合材料高效加工的潜在关键技术，新兴的高速切削基础研究不足导致工艺优化缺乏科学依据，尤其复合材料在高速切削的极端苛刻环境的摩擦效应研究成为技术应用的瓶颈。项目聚焦典型铜基复合材料高速切削过程中的热-力耦合作用下的刀具-工件-切屑多界面摩擦学行为，揭示特定切削过程的摩擦学机理。选取典型重要的铜基复合材料，模拟切削过程研究摩擦引起的复合材料晶粒拉伸/细化、相变、界面开裂/愈合等微观组织演变，探讨切削过程自润滑铜膜的形成和演化的影响因素，揭示摩擦效应下的切屑和已加工表面形成机理；建立考虑材料微观组织特性的高温高应变率动态力学性能本构模型，基于三维有限元法分析高速摩擦下的应力场/温度场分布规律，研究应力场/温度场分布对刀具磨损形态和切削力时变特性的影响，揭示刀具磨损和破损规律，以推动铜基复合材料高速高效精密加工技术发展，丰富高性能金属基复合材料高速切削摩擦学理论。

High-speed cutting is a potential key technology for efficient processing of high-performance copper matrix composites for a wide range of applications. The shortage of basic research on high-speed cutting leads to the lack of scientific basis for process optimization. In particular, the study of friction effect of composite materials in the extremely harsh environment of high-speed cutting has become a bottleneck in the application of technology. The project focuses on the multi-interface tribology behavior of tool-workpiece-chip under thermal-mechanical coupling in high-speed cutting of typical copper matrix composites, and reveals the tribology mechanism of specific cutting process. The copper matrix composites with important industrial application value are selected. The microstructure evolution of composites, such as grain stretching and refining, phase structure transformation, interfacial cracking/healing caused by friction effect, is studied by simulating cutting process. The influencing factors of self-lubricating copper film formation and evolution in cutting process are discussed. The formation mechanism of chips and machined surfaces under friction effect is revealed. The constitutive model of dynamic mechanical properties at high temperature and high strain rate is established considering the microstructure characteristics of materials. Based on the three-dimensional finite element method, the distribution of stress field/temperature field under friction effect is analyzed. The influence of stress field/temperature field distribution on tool wear morphology and time-varying characteristics of cutting force is studied, and the rule of tool wear and breakage is revealed in order to promote the development of high efficiency precision machining technology and enrich the high speed cutting tribology theory of high performance metal matrix composites material.