Optimizing the cutting edge geometry of micro drill based on the entropy weight method

Micro drill structures have significant effect on the cutting performance, especially the major cutting edge geometry. In this work, five different sections on major cutting edge of micro twist drill were dissected to perform the simplified orthogonal cutting simulation. The results indicated that different sections on major cutting edge show the obvious cutting performance difference because of different rake angles. The entropy weight method in mathematical statistics was used to evaluate the comprehensive cutting performance of different sections on major cutting edge. According to the total score from entropy weight method, the rake angles for five different sections were optimized to 19°, 21°, 23°, 25°, and 27°. Micro drilling simulation result showed that micro drill with the optimized rake angle presented the better cutting performance with a decrease in stress and pressure distribution.