微細表面テクスチャを有するCBN工具によるInconel 718の高速切削加工

抄録

Nickel-based superalloys such as Inconel 718, which are widely used especially in the aircraft industry, are known to be among the most difficult-to-cut materials because of their mechanical and chemical properties, and tools used for this purpose have extremely short lifetimes. Recently, cubic boron nitride (CBN), which is the second hardest of all known materials, has received significant attention as a material for cutting tools and has already established itself in many fields of application. However, the performance of CBN tools is still insufficient for practical use, especially in the high-speed machining of Inconel 718. To overcome this problem, we first conducted orthogonal cutting experiments on Inconel 718 and performed cross-sectional observations of the CBN cutting tool in order to identify its wear mechanisms in continuous cutting operations under high-speed machining conditions (300 m/min). Based on the results, a CBN cutting tool with a textured flank face was newly developed to improve the cutting tool life. Experimental results showed that micro grooves generated on the flank face significantly suppressed the cutting edge chipping and remarkably extended the CBN tool life during high-speed machining of Inconel 718.