Analysis of interface temperature transfer of CFRP/ Aluminum honeycomb sandwich structure during ultrasonic assisted milling

The sandwich structure composed of carbon fiber reinforced composite (CFRP) and aluminum honeycomb core is widely used in aerospace and other fields because of its excellent performance.In the traditional milling process, due to the significant difference in material properties, it is easy to produce local high temperature at the material interface, causing resin thermal degradation, fiber pulling out, honeycomb tearing and other damage, which seriously affects the processing quality and the service performance of components. In order to predict the interface temperature rise effectively, the temperature transfer law between interfaces during milling process was analyzed by combining experiment, theoretical analysis and simulation. A milling model of sandwich structure was constructed in ABAQUS software, and the theoretical heat transfer mode between the two materials was analyzed. In addition, this study uses ultrasound-assisted milling technology and traditional milling processing to conduct comparative experiments, through experiments to verify the feasibility of the simulation model, and through experiments and simulation to verify the model. The results show that when the ultrasonic amplitude is 3micrometer, the vibration frequency is 24KHz, the speed is 10000 RPM, and the feed rate is 60mm/min, the temperature transmitted to the aluminum honeycomb core layer of the CFRP composite layer by ultrasonic milling is reduced by about 29% compared with the traditional milling method without ultrasonic. In addition, the core tearing of the aluminum honeycomb surface after ultrasonic milling is reduced by about 25%. In the case of a feed rate of 40mm/min, the temperature transmitted to the aluminum honeycomb core layer during ultrasonic milling of the CFRP composite layer is reduced by about 31% compared with the traditional milling method without ultrasound. In addition, the core lattice tearing of the aluminum honeycomb surface after ultrasonic milling is reduced by about 29%. It was found that milling CFRP laminates at a feed rate of 40mm/min resulted in lower temperature conduction to the honeycomb core layer and less damage to the honeycomb core layer.