关键词: Sierpinski分形, 微织构, 切削性能, 切削仿真, 切屑流动

Abstract: The preparation of specifically shaped micro-textures on the tool rake face has proven effective in reducing cutting forces,lowering cutting temperatures,enhancing tool performance,and extending tool life. The size and geometry of micro-textures significantly affect the cutting performance. However,the current design of micro-textured tools mainly focuses on simple,compound or bionic geometric patterns,and their cutting performance still needs to be further improved. In this study,a novel Fractal-Textured Tool (FTT) incorporating a Sierpinski carpet pattern was designed based on fractal theory. Orthogonal cutting simulations of AISI4340 alloy steel were conducted to evaluate the cutting performance of the FTT in comparison with a regular square-pattern Micro-Textured Tool (MTT) and a Non-Textured Tool (NTT). Simulation results demonstrate that,compared to MTT and NTT,the FTT more effectively reduces the actual tool-chip contact area,regulates chip flow,and achieves a more uniform distribution of normal contact stress on the rake face,thereby mitigating stress concentration and lowering peak stress levels. The FTT also significantly reduces cutting forces,particularly under high feed rates,with the largest observed reductions in average main cutting force and feed force reaching 16.3 % and 14.3 %,respectively. Moreover,the FTT exhibits a more uniform temperature distribution on the rake face,preventing local heat accumulation and enhancing cooling performance. Under increasing feed rates,the average temperature rise at the cutting edge of the FTT is the lowest among all tools tested,limited to just 7.5 %.

Key words: Sierpinski fractal, micro-texture, cutting performance, cutting simulation, chip flow