The design and cutting performance of variable pitch solid ceramic end milling tools

Ceramic tools are widely employed for high-speed cutting of nickel-based alloys due to their good high-temperature mechanical properties, thermal stability, high corrosion resistance, and oxidation resistance. Aiming at the drawbacks of ceramic tools, such as high brittleness and limited ability to withstand vibration and shock loads, the vibration reduction performance of the tool is improved by geometry design, which can effectively improve the tool life. In this paper, to reduce the cutting vibration and improve the tool life of the solid ceramic end milling tool, based on the research of vibration reduction mechanism and milling stability analysis, a new type of variable pitch solid ceramic end milling tool was developed through tool geometry design. The excellent cutting performance of the designed solid ceramic end milling tools is verified by experiments. The research results indicate that the inter-tooth angle distribution of the three types of optimized variable pitch milling tools were 93°-91° − 88°-88° (T1), 95°-85°-85°-95° (T2) and 83°-83°-98°-96° (T3), respectively. Compared with the equal pitch milling tool, the tool life of T1 and T2 was examined to increase by 30% and 40%, respectively. In addition, the cutting force was found to decrease by 13.6% and 9.4% respectively, while the surface roughness of the machined workpiece decreased by 21% and 18.4%, respectively. Fewer defects were observed on the machined surface of the workpiece, leading to a significant improvement in machining quality. However, the cutting performance of T3 was found to be subpar in the cutting test. Insufficient tooth strength and increased vibration due to large mass eccentricity were found to be the primary contributions for the decreased cutting performance.