| abstract |
Chemical wear is very important when cutting highly rigid, ductile iron metals such as austempered ductile iron (ADI) or steel because of the high temperatures on the cutting edge. In said uses, silicon nitride or SiAlONe are not thermodynamically stable enough, while aluminum oxide-based cutting materials can be used to a limited extent only because they have low resistance to thermal shocks and have low ductility. The invention therefore relates to a hard ceramic material which is made from a powder mixture of Si3N4, Al2O3, AlN and oxides of at least one of the elements Mg, Ca, Y, Lu, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb. |