Study of micro-hole pecking drilling process for high volume fraction SiCp/Al7075 composites

A novel micro-hole pecking drilling process on high volume fraction SiCp/Al7075 composites was proposed in this paper. Firstly, the comparison of cutting volume to analyze the magnitude of the cutting force during straight and inclined drilling was performed and a prediction analysis was made. Two main conclusions were obtained by the study. (1) If the cutting volume is larger within the same time period, the cutting force will be larger. (2) The intensive level of step volume can predict the location of edge defects at the entrance and exit of inclined drilling. Secondly, a two-phase simulation model was established with silicon carbide (SiC) containing 55% volume fraction inside the material, and simulations were performed for drilling. Finally, a three-factor, three-level straight drilling response surface methodology (RSM) test was designed, and the two-factor, three-level inclined hole drilling test designed for the straight hole machining parameter law, obtained the test cutting force and verified the correctness of the cutting volume conclusion 1 and the micro-hole pecking drill simulation. The optimum process parameters for micro-drilling were obtained from the straight hole test study and verified by a better exit and entrance profile. The optimum process parameters for micro-drilling were obtained based on the experimental study of inclined holes and verified the cutting volume conclusion 2. This study provides a theoretical prediction, simulation model and machining process for micro-hole pecking drilling of high volume fraction SiCp/Al7075 composites.