Performance analysis of Nano Engineered Diamond coated tools for machining of AA2124/SiC<inf>p</inf> composite material

Aluminum based metal matrix composites (Al-SiC) are widely used in automotive and aerospace industries due to its high strength to weight ratio, high wear resistance, and higher thermal conductivity. Though it has lots of commercial applications, machining of this MMC still a challenging task due to its hard SiC reinforcement in the soft aluminum material. These two phases cause adhesive and abrasive wear on the cutting tool. Hence tooling with a property of combined hardness and toughness required to machine this material effectively. In this connection, CVD diamond on WC-Co is considered as the suitable cutting tool for the precise machining of this MMC material. Even though it is commercially available, the usage is limited due to the poor interfacial adhesion of CVD diamond on WC-Co leads to coating delamination. In this work, the boron doped diamond (BDD) and boron doped graded layer diamond coating (BMTN) on WC-Co were considered. Machining experiments were conducted on a lathe using AA2124/SiCp MMC material to evaluate the wear performance of the BMTN, BDD, MCD (Microcrystalline diamond coating) and NCD (Nanocrystalline diamond coating) coated cutting inserts. The tool wear results indicate that the BMTN outperformed in comparison with MCD and NCD coated tool inserts.