Studies on drilling processes of intermetallic compounds

Intermetallic compounds have high-specific strength, good creep resistance and excellent oxidation and corrosion resistance at high temperatures. Those good mechanical properties make intermetallic compounds very promising structure materials in industries. Ni3Al and Fe3Al are two typical intermetallic compounds. This paper focuses on machinability and tool wear mechanism of PVD TiAlN coated cemented carbide tool in drilling of Ni3Al and Fe3Al. The influences of cutting speeds on tool wear and machined surface roughness were investigated. The tool wear mechanism was analyzed using scanning electron microscopy (SEM) and EDX analysis. Chips were analyzed by SEM and the machined surfaces were examined by surface roughness measurement instrument. Tool life when drilling of Ni3Al is shorter than that of Fe3Al. The built-up-edge (BUE) could be formed on the cutting edge in drilling of Fe3Al, and no BUE was observed of Ni3Al at the cutting speed of 29 m/min.