Machinability analysis in drilling woven GFR/epoxy composites: Part I – Effect of machining parameters

The present paper deals with the effect of machining parameters (feed, speed and drill diameter) on the thrust force and machinability of woven glass fiber-reinforced epoxy (GFRE) composites. The selected machinability parameters were delamination size, surface roughness, and bearing strength. The results show that, delamination-free in drilling GFRE composites was not observed, in the range of the investigated cutting parameters. Surface roughness instrument can be used as an indication for the position of the internal delamination damage in drilling GFRE composites. The high values of correlation coefficients between thrust force and the machinability parameters confirm the importance of reducing the thrust force to improve the load carrying capacity of composite structure assembled by rivets or bolted joints.