Research of bamboo rat tooth bionic bit structural design and cutting mechanism for CFRP drilling

Abstract

The holes are very easy to appear delamination and burr during CFRP drilling. The tool geometry has a great impact on the hole making. In this paper, according to the principle of bionics and structural features, a novel bionic drill bit was designed. The mathematical model of the lower incisor teeth occlusal movement was established. The cutting mechanism of the bamboo rat lower incisor on PW-CFRP material was studied. It was found that the curvature of the contour curves of the front cutter faces were constantly changing, which was conducive to the removal of chips. The curvature change of the contour curve of the rear cutter surface is small and the curve is relatively smooth, which is conducive to reducing friction. The mathematical modeling analysis was carried out on the feeding process of bamboo rats, and the mathematical relationship between the bite radius R and the cutting angle θ was obtained. The optimal cutting angle θ = 10° and the corresponding biting radius R = 40 mm were obtained by finite element simulation. The surface cutting quality of bamboo rat's lower incisors is better than that of ordinary cutting tools. The novel bionic tool can effectively reduce the burr and delamination of the exit layer.