Analysis of possibilities for modification of drill bit geometrical parameters used to drill holes in composite materials of various composition

摘要

Purpose - The purpose of this paper is to investigate the concept of new drill bit geometry adjusted to a given composite type. This paper explores the possibility of drilling in composites without negative effects such as: delamination, rapid tool wear, matrix burns, pulling out of fibers, etc. Design/methodology/approach - Appropriate modification of drill bit geometries applied to composite materials include, among other things: modifications of point angles, reduction of chisel edge width, modification of drill margins and proper preparation of drill bit corners. Findings - Description of tool geometry for drilling of different types of composites, in particular drilling in parts included free grain surfaces but also drilling at a different angle than 90°. Research limitations/implications - Geometrical details of the tool for drilling are depended on the type of composite. Practical implications - Making of montage holes in parts made of composites without negative effects during drilling. Originality/value - Analysis of the current state of knowledge shows that there are insufficient solutions in terms of new drill geometry for drilling of composites. Existing solutions do not guarantee adequate stability and repeatability of the cutting process. It is necessary to create new geometry drills permit the elimination of negative phenomena during drilling.