Abstract
The failure characteristics and the cutting ability of TiC added alumina ceramic tool when face milling SKD 11 were studied. The tool failures when milling SKD 11 with a hardness over HRC 50 were grouped into three types : wear caused gradually by adhesion and peeling off of the work material onto the cutting tool (type 1), large fractures caused rapidly by scooping on the rake face and chipping on the cutting edge (type 2), and large fractures caused suddenly by thermal cracks in the rake face (type 3). Which type of failure occurred to cutting edge was related to the cutting speed, engage angle and disengage angle. The engage and disengage angles also influenced the tool life ; the disengage angle had a greater influence than the engage angle. In the case when the cutter had a bigger diameter than the work width, the more the disengage angle increase, the more the tool life became long. On the other hand, in the case when cutter had a smaller diameter than the work width, as the engage and disengage angles became larger, i. e., the more the cutting width became wider, the more the tool life became long. There is the most appropriate cutting speed which to extends the tool life.
