Machinability of Sintered Carbon (4th Report)

Cutting Performance and Wear Behaviour of Ceramic Tools When Turning Three-Phase Sintered Carbon

Abstract

In this paper, the cutting performance and the wear characteristics of ceramic tools such as Al₂O₃, Al₂O₃+ZrO₂, Al₂O₃+ TiC and Si₃N₄ are presented when turning three-phase sintered carbons containing nongraphitized materials and are compared with these of the cemented carbide tool K 10. Further, since the wear of alumina ceramics is influenced by surrounding moisture, cutting tests are carried out on the sintered carbons containing water. The wear rate of alumina ceramic tools is slower for carbon phase (1500°C) than for graphite phase (2500°C). This behaviour is different from that of K 10 and Si₃N₄. In particular, the wear pattern consists of two areas of wear and carbon adhesion in the cutting of carbon phase. The same behaviours are also observed when turning two-phase sintered carbon. A tendency of wear rate corresponds to that of coefficient of friction in rubbing tests.