Patent ID: 6790252
Filing Date: 2004-09-14
Classification: B22F,C22C

Abstract:
A process of making an article comprised of a tungsten-carbide-cobalt alloy with or without an additive of one or more of tantalum, cobalt-nickel, nickel-tantalum, tantalum-carbide, titanium-carbide, niobium-carbide, chromium-carbide, titanium-nitride and diamond dust, comprising the steps offorming a homogeneous mixture of polygonal-shaped powder tungsten-carbide-cobalt and a polygonal-shaped powder additive and a binder including wax and a high molecular weight polyolefin polymer wherein the additive is present in the range of from about 0% to about 7% by weight of the article, injecting the mixture under heat and pressure into a metal injection mold to form a green preform of the article; immersing the green preform in one or more of mineral spirits or n-propyl bromide or a liquid alkane, to dissolve and remove the wax and convert the green preform into a brown preform of the article; and sintering the brown preform to remove the remainder of the binder and to densify the brown preform into an article comprised of tungsten-carbide-cobalt with or without an additive, the article having a density not less than 98% of theoretical when cobalt is present in an amount not less than about 3% by weight of the article.