In order to study the influence of double chamfer parameters on drilling performance, a finite element J-C thermodynamic coupling damage model was established for double chamfer TBT drilling and processing of 7075-T651 aluminum alloy using Abaqus software. Theoretical analyses were conducted on the force analysis of the ideal contour of the deformation area during the drilling process, the material flow mode of the chamfered cutting edge, the force analysis of the cutting force, and the conveniently calculated drilling force model. The torque formula and axial force formula of the drilling force model for the chamfered cutting edge of TBT drilling were obtained. Research shows that the theoretical formula of the established drilling force model for the chamfered cutting edge of TBT drilling can be applied to the calculation of the torque and axial force of the chamfered cutting edge of TBT drilling. The distribution laws of the chamfer cutting edge width and chamfer Angle on the axial force and torque of the TBT drill were obtained. It is concluded that when designing the bevel cutting edge of TBT drilling, a bevel cutting edge width of 0.1–0.2 mm and bevel angles of 30º and 60º can obtain a smaller axial force.