Research On Cutting Performance Of Coated Cutting Tools By A New Impact Test Method Considering Contact Stress Condition Caused By Segmented Chips

The generation of segmented chip will cause unstable vibration of cutting force and produce high-frequency stress impact on the cutting tool. The segmented chip morphology and contact stress between chip and flank face of coated cutting tool were studied by cutting experiments. It was found that the average contact stress of the coated tool was 4.9 GPa and the alternating frequency reached 22 kHz. A new high-frequency impact test method was used to simulate the loading condition of coated tools in the cutting experiments. The results showed that the cutting performance of the coated tool was related to the impact fatigue resistance. In the case of a high feed rate (above 0.1 mm/rev) or high preloading depth (7.51 mu m and 9 mu m), TiSiN/TiAlN bilayer coating shows better performance, compared with TiSiN/TiAlN nanolayer coating. However, in the case of low feed rate (less than 0.1 mm/rev) or low preloading depth (18 mu m), TiSiN/TiAlN nanolayer coating shows better performance. Cutting conditions and coating structure could match to get optimized cutting performance of coated cutting tools.