Research On Drilling CFRP Laminate With A Thin Woven Glass Fiber Surface Layer Using Plane Rake Faced Twist Drill

The delamination produced during drilling CFRP will affect its structural strength seriously. Delamination is closely related to the thrust force during drilling, which is closely related to the tool, so it is particularly important to choose the tools with appropriate geometric structure. Many scholars used tools with different geometric structure to drill CFRP, and then conducted the drilling damage analyses and drilling mechanism researches. It finally came to a conclusion that drill with special structure had certain advantage compared with common twist drill in the drilling process. In this paper, a new type of plane rake faced twist drill was used to drill the CFRP laminate with a thin woven glass fiber surface layer. Experimental results showed that plane rake faced twist drill along cutting edge had a constant reference rake angle value, which caused the plane rake faced twist drill generated smaller thrust force and less drilling damage than the common twist drill. As the reference rake angle of plane rake faced twist drill increased, the thrust force and drilling damage decreased. It was revealed the inhibition of the thin woven glass fiber surface layer on the drilling damage at entrance and exit. Finally, it was proposed that when plane rake faced twist drill was used to drill CFRP laminate with a thin woven glass fiber surface, 46° reference rake angle should be selected.