Cutting Performances of Coated PVD in High Speed End Milling of Aged Inconel 718

Inconel 718 is a material exhibiting characteristic that are able to maintain strength and integrity at elevated temperatures, but it is well known as a material with poor machinability. This paper presents a study of the performance in high speed machining of TiAlN/AlCrN nanomultilayer PVD coated Inconel 718 with minimum lubrication. Investigations have been made into the effects of cutting speed, feed rate and depth of cut (DOC) on the tool life. A toolmakers microscope and a scanning electron microscope (SEM) were used to examine the tool wear and chemical attrition, respectively, on the cutting tool during machining. In the machining of aged Inconel 718, the cutting tool experienced attrition, abrasion and notch wear throughout the experiment. Notch wear was found to be the dominant failure mode during milling; this wear appeared severe when localized flank wear reached the critical zone. The influence of radial depth despite the cutting speed, well known as having the most significant effect on tool life, is also discussed