Search results

The purpose of this paper is to analyze machinability of CFRP, GFRP, GLARE-type composites in drilling process taking into account their features and properties (the geometric characteristics, the volume fraction and the mechanical properties of the individual components of the composite). Drilling in non-plan surfaces and slope drilling.

The tests were carried out in two stages: perpendicular drilling of materials such as GLARE with special drill bits, and drilling of composite structures with non-planar surfaces made of unidirectional carbon fiber prepregs, using the modified special drill. Measurement of cutting forces and torque, stress distribution (photoelastic method) and a visual assessment of defects occurring during drilling allowed to determine the relationship between the type and geometry of the composite drill.

Identified great effect of kind of composite on the machinability of these materials has substantiated modification of the standard geometry of drills and matching this geometry to specific properties of the various type of composites.

Drilling of assembly holes for aerospace parts.

New type of drill geometry for different type of composite.

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.

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.

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°.

Geometrical details of the tool for drilling are depended on the type of composite.

Making of montage holes in parts made of composites without negative effects during drilling.

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.