CNC선반 절삭에서 이송속도 및 절삭속도의 변화에 따른 재질별 표면조도에 관한 연구

A Study on the Surface Roughness by Material in CNC Lathe Cutting according to the Change in Feed Rate and Cutting Speed

This study has performed cutting tests by material to investigate the change in surface roughness of the workpiece given the change in the correlation between cutting speed and feed rate during CNC lathe cutting. In the test, SUM21, Al alloy 2024, and 6:4 brass was processed based on the cutting conditions of a regular work standard and then the changes in surface roughness based on Center Line Average (Ra) after increasing or decreasing cutting conditions was investigated. As a result, SUM21 generated the best Ra in 180m/min, 0.07mm/rev; Al alloy 2024 generated the best Ra in 400m/min, 0.07mm/rev; and 6:4 brass generated the best Ra in 220m/min, 0.07mm/rev. Furthermore, precise Ra was generated in general when feed rate was reduced while cutting speed was fixed; and all 3 materials generated poor Ra values when cutting speed and feed rate were raised simultaneously. When both cutting speed and feed rate were raised by 30%, there was no significant 6:4 brass Ra, 6.1% reduction only.