Experimental investigation of delamination formed by bone drilling

Abstract

Bone drilling is a common method for fixing implants used in bone fractures. Because of the fibre-reinforced composite structure of bone, parameters such as feed rate, spindle speed and drill type affect the hole surface quality. After drilling, the quality of the bore surface, burr formation and delamination at the hole entrance and exit affect the ability of the screw to cause implant failure and fusion problems of the fracture. For this reason, it is very important to conduct drilling with optimum speed and feedrate values. In this study, the effects of processing parameters on hole surface quality and delamination were studied experimentally. In the experiment, bovine bone, which has similar structural properties to human bone, was used. The hole surface quality and delamination formed at the exit of the hole were examined for three different feed rates and spindle speeds. As a result of the experiments, it was seen that the feed rate had more effect on both delamination and hole surface quality than the spindle speed. It was also determined that the cortical part of the bone and the cancellous part of the bone affected the production of heat and drill wear differently.