Experimental investigation into the effects of changing the various curves of step drill cutting edges & cutting parameter on induced delamination in d rilling Woven-GFRP

Drilling is one of the most important operations for manufacturing, assembly and disassembly of the products. Drilling of composite laminate by traditional twist drill tool caused of delamination, fiber exit and other defects. A major factor in composite delamination is the tool geometry and feed rate. In this paper, by comparing the experimental method and analysis by software, the affected zone of cutting forces on the composite laminate obtained during the drilling process, then is paid investigate the effect of tool geometry in step drill by special shape (concave and convex cutting edges) in reducing of composite delamination. The goal was determination of the simultaneous effect of feed rate, spindle speed and tool geometry has on the phenomenon of layered composites. Due to the large number of experiment on the samples were statistically analysis of variance method for the reduction experiments and generalizing the results has been applied. The results show that the optimal values of feed rate and spindle speed also step drill tools with the cutting edge concave - convex, has the lowest delamination create.