Abstract: The present invention relates to a cemented carbonitride alloy in which the toughness has been improved by the incorporation in the structure of whiskers of nitrides, carbides and/or carbonitrides of titanium, zirconium and/or hafnium.

Abstract: The present invention relates to a ceramic cutting insert containing whiskers for chip forming machining of steel and having improved mechanical, thermal and wear properties. The insert comprises besides the oxide-based matrix 5-50% by volume, preferably 10-40% by volume, of homogeneously dispersed whiskers of carbides, nitrides and/or borides of titanium and/or zirconium and, where applicable, solid solutions thereof. A part of the whiskers may be replaced by whiskers of silicon carbide. The properties of the composite material can be further modified by coating the whisker material with thin layers. The whiskers reinforced cutting material shows an improved toughness behaviour and resistance to thermal crack formation without having a negative influence on the wear resistance to any appreciable extent.

Abstract: The present invention relates to a ceramic cutting insert containing whiskers for chip forming machining of steel and having improved mechanical, thermal and wear properties. The insert comprises besides the oxide-based matrix 5-50% by volume, preferably 10-40% by volume, of homogeneously dispersed whiskers of carbides, nitrides and/or borides of titanium and/or zirconium and, where applicable, solid solutions thereof. A part of the whiskers may be replaced by whiskers of silicon carbide. The properties of the composite material can be further modified by coating the whisker material with thin layers. The whiskers reinforced cutting material shows an improved toughness behaviour and resistance to thermal crack formation without having a negative influence on the wear resistance to any appreciable extent.