The impact of tool point angle and interlayer gap width on interface borehole quality in drilling CFRP/titanium stacks

Abstract Although substantial research work has been conducted in order to understand and improve the drilling of multi-material aerospace stacks, some key aspects related process tool parameters their impact on interface quality still need be addressed. This paper reports investigate point angle interlayer gap width borehole quality, focussing region. A number tests were carried out using tools with different angles CFRP/titanium stacks widths. The results show that damage CFRP surface is caused by titanium layer, as upwards-travelling chips penetrate into stack interface. An increase larger entry burrs surface, which attributed correlation between thrust force capability low remove generated skidding. introduction an promotes ingress interface, thereby leading more pronounced damage.