A torque and thrust prediction model for drilling of composite materials

In this paper, the authors present a mechanistic model for use in predicting thrust and torque during composite materials drilling. They specify the number of coefficients to be experimentally determined and provide a detailed analysis of the problems associated with the action of the chisel edge. Their theoretical approach was suggested by the observation that during a drilling process the prerequisites for orthogonal fiber cutting are met for an infinitesimal instant. Hence their decision to simulate a conventional drilling process by developing a model with only two semi-empirical coefficients. The method proposed is comparatively user-friendly since the semi-empirical coefficients concerned can be determined without difficulty by means of simple linear relations. The results obtained were satisfactorily validated by comparing the test findings with the corresponding theoretical data and it is possible to conclude that the model affords a focused approach to the definition of the most appropriate drill geometry and cutting parameters in composite materials drilling.