High Speed Machining of Inconel 718 with Ceramic Tools (2nd Report)

Abstract

In order to cut the Ni-based super alloy Inconel 718 with high speed, a TiC whisker reinforced alumina ceramic tool was newly developed. In machining the Inconel 718, while a SiC whisker reinforced alumina ceramic tool showed a good performance in respect to notch wear at cutting speeds of up to 300 m/min, the tool had a large thermal wear at the higher cutting speeds because of its thermal instability to the Inconel 718. A TiC added alumina ceramic tool, to the contrary, indicated good wear resistance even at a cutting speed of 500 m/min because of thermal stability to the alloy, while the tool had a large notch wear at relatively low cutting speeds. Therefore, the TiC whisker reinforced alumina ceramic tool was developed for the purpose of giving advantages to both the SiC whisker and TiC added alumina ceramic tools. However, the tool had damage, mainly chipping, under heavy cutting conditions, while the tool showed good performance for the notch wear at low cutting speed. The reason of the chipping must be that TiC whiskers used in this test had large distributions in size, diameter and length. © 1995, The Japan Society for Precision Engineering. All rights reserved.