The temperature distributions along the primary cutting edges and on the flank surfaces are calculated numerically using the variational approach of the three-dimensional finite element method for two different cross-sectional shape designs of a drill body. This is to illustrate that the different cross-sectional shape designs of a drill body have some degree of influence on the drill temperature fields. The calculated results demonstrate that the possibility of a longer drill life from the thick web drills with curved primary cutting edges is due to a more uniform temperature distribution and a relatively lower temperature along the primary cutting edges and on the flank surfaces. W.-C. Chen Vol. 23, No. 3 investigated the effects of the temperature distribution of a drill with five different geometry parameters and three different operating conditions by thermocouples. Recently, Agapiou and DeVries [8,9] studied the average drill point temperature by both analytical and experimental approaches. In their analytical study, the temperature was computed by analyzing one-dimensional heat equation. In their experimental study, an iron-constantan thermocouple was used to measure the average flank temperature using the Powder Metallurgy (P/M) 304L stainless steel materials which have different thermal properties. Chen [10] and later Fuh, Chen, and Liang [11]
developed the temperature distributions along the primary cutting edges and on the flank surfaces of a full scale conventional twist drill by employing the variational approach of the three-dimensional finite element method. In their study, the quadratic hexahedron solid elements with twenty nodes in each element were used to model the complex configuration of a twist drill. In addition to calculating the steady and transient temperature responses at different cutting conditions, the effects of the penetration depth, the web thickness, and the helix angle on the temperature distributions along the primary cutting edge and on the flank surfaces were also investigated.