Cemented carbide body
AssigneeSandvik Intellectual Property AB
InventorMarian Mikus
Life of this patent
Estimating the term…
Abstract
According to the present invention there is now provided a body cemented carbide provided with at least one wear resistant layer, which body contains a toughness increasing surface zone. Increase in toughness is obtained due to the presence of a surface zone having increased WC grain size and/or increased Co content. The invention is most suitable for WC-Co cemented carbides.
Claims14
A WC+Co based cemented carbide body, with a carbon content below the saturation point, with or without addition of<about 3 weight % grain growth inhibitors having a nominal average WC grain size of from about 0.3 to about 3 μm containing from about 3 to about 12 weight % binder phase, comprising at least one of the elements Co, Ni, Fe with about 5 to about 100 μm thick surface zone different from the interior of the body, said surface zone being free of eta phase and wherein within the entire thickness of the surface zone the WC grains have an average grain size within the range of ±20% the same as the nominal average WC grain size, together with an average Co content at least 10% higher than the nominal Co content.
WC+Co based cemented carbide body, with a carbon content below the saturation point with addition of<about 3 weight % grain growth inhibitors having a nominal average WC grain size of from about 0.5 to about 1.7 μm containing from about 3 to about 12 weight % binder phase, comprising at least one of the elements Co, Ni, Fe with about 5 to about 30 μm thick surface zone different from the interior of the body, said surface zone being free of eta phase and wherein within the entire thickness of the surface zone the WC grains have an average grain size within the range of ±20% the same as the nominal average WC grain size, together with an average Co content at least 30% higher than the nominal Co content.
Dependencies are inferred from the claim text.