Effect of Cryogenic Conditions on the Drilling Performance of Carbon-Carbon (C-C) Composites

Abstract

C-C composite is a kind of typical difficult-to-machine materials due to its high hardness, high strength, and obvious anisotropy features. But, water-based or oil-based coolant cannot be used during its machining process. As a result, the machining defects, including burrs, orifice ripping, and interlayer delamination, are always unavoidable. In this article, taking the liquid nitrogen as coolant, C-C composite cryogenic drilling is researched experimentally. Taking the way of LN2 external spray cooling, a series of cryogenic drilling experiments were designed. Comparing with dry drilling, the thrust force was reduced, the machining defects were significantly inhibited, and a better roundness of holes was achieved in cryogenic drilling. It indicates that cryogenic condition has a positive effect on improving the C-C composite drilling quality.

Design and Analysis of CFRP Drilling by Electrical Discharge Machining

“…In addition, the abrasive nature of the reinforcement and adhesive wear constantly deteriorate the cutting edges resulting in large variations in the final diameter [ 9 ]. Alternatives such as the application of lubricants or cryogenic coolants can improve the final process performance, but at the same time increase the negative environmental impact or alter the composition of the composite material [ 11 , 12 , 13 ].…”