Drilling analysis of woven glass fiber-reinforced/epoxy composites

This article deals with the effect of drilling parameters (feed, speed, and drill pre-wear) on the machinability parameters (thrust force, torque, peel-up and push-out delaminations, surface roughness, and bearing strength) in drilling woven glass fiber-reinforced. The results show that at high feeds (0.45 mm/rev), the drill point acts as a punch that pierces the laminate with approximately constant push-out delamination size irrespective to the value of the thrust force. Surface roughness increases with the increase of drill pre-wear due to the generated heat that assisted by the low thermal properties of polymeric composites. Drilling at high feeds reduces the stiffness of the specimens and its ultimate bearing loads. Artificial neural network and multivariable regression models were developed for predicting the bearing strength of drilled holes.