A comparative analysis of machining efficiency between conventional drilling and ultrasonic-assisted drilling of CFRP/Al stacks

CFRP stacks combined with aluminum alloys are commonly used in vehicles because they offer a great balance of high mechanical properties and low weight. Ultrasonic-assisted drilling (UAD) is a new process designed to enhance hole quality in conventional drilling (CD). In this paper, the effect of UAD process on CFRP/Al stacks compared with CD process was investigated using comparative experimental. The experimental findings indicated that UAD greatly lowers the cutting forces for CFRP/Al, achieving maximum reductions of 22.4% for the CFRP layer and 17.1% for the aluminum layer. And UAD reduced the cutting temperature at the stack entrance and interface by 15.7% and 20.8%, respectively. Meanwhile UAD effectively prevented delamination and enhanced the quality of the processed CFRP layer's surface. The findings in this study suggest that the UAD process is suitable for low-damage processing of CFRP/Al stacks.