Influence of cutting tool geometry, feed rate and cutting fluid on the machinability of Inconel 751

Inconel represents a family of nickel-based super alloys with a wide range of application including components that work at high temperatures. Despite of this, nickel-based super alloys are generally known to be one of the most difficult materials to machine. In this paper, attention is focused on the machinability of Inconel 751 which is a nickel-based super alloy normally used to manufacture exhaust valves of internal-combustion engines. In this case, an experimental investigation where a series of dry and wet rapid facing trials (turning) using coated carbide tools were performed. Metal removing process was carried out for two different feed rates and two different tool geometries. For indirectly quantifying the tool wear, the machined surface profile has been measured using a centesimal dial gauge. Moreover, cutting tools have been analysed with a scanning electronic microscope. The results provide important practical information about the machinability of Inconel 751.