Low frequency vibration aided drilling technology for Al /CFRP laminated structure

WANG Shuai-fei, WANG Fu-ji, LI Sheng-kai, WANG Xiao-da, JIA Zhen-yuan
(School of Mechanical Engineering, Dalian University of Technology, Dalian 116024, China)

Abstract: Aiming at the problem that the unclear removal mechanism of CFRP could not ensure machining quality of Al and CFRP at the same time during low-frequency vibration-assisted drilling process of Al/CFRP laminated structure, the tool path during vibration-assisted drilling was analyzed by theoretic method. Based on this, the effect of low frequency vibration on material removal and processing quality at Al entrance, CFRP exit and hole wall of the laminated structure was revealed. The influence of low-frequency vibration parameters was further studied, a drilling platform including lowfrequency vibration tool holder was built, based on which lowfrequency vibration-assisted drilling experiments with special designed tools for CFRP at different amplitudes were conducted. The results indicate that low-frequency vibration can effectively achieve aluminum alloy chip breaking, avoiding scratching of long chips and improving the processing quality of Al part. The introduction of low-frequency vibration can increase the maximum axial force and excessive amplitude can exacerbate tear damage of CFRP at the exit and reduce the quality of drilled hole wall.

Key words: drilling of laminated materials; low frequency vibration; amplitude; processing quality