Powdered metal article

Abstract

Abstract 1,237,244. Powdered metal bodies. CRUCIBLE Inc. June 17, 1968 [Sept. 11, 1967], No.28840/68. Heading C7A. A metal body is composed of compacted particles of a high speed tool or die steel composition containing a metal, variety Ti, V, Mo, Zr, Nb, Ta or W, which is reacted with C, O or N to form carbides, oxides or nitrides, respectively, which are evenly distributed throughout each particle, the body having a hardness of at least 58Rc. High speed tool steels are defined to have the composition :- Co 0-12% Mn up to 2% Si up to 1% S up to 0À5% Fe and impurities-balance Die steels are defined to have the composition:- The carbide, oxide or nitride may be produced in the particles by (a) being present in the melt from which the particles are made, or (b) making the particles containing the metal in pure form and then reacting with the C, O or N with subsequent diffusion of the resulting compound throughout the particles. Compacting is effected by heating a container of powder (preferably of minus 30 standard mesh size or finer) and then compressing in a die or autoclave. The hardness of at least 58Rc is produced by austenitizing, quenching and tempering. The evenly dispersed carbide, oxide or nitride leads to the substantial absence of outof-roundness of the body after hardening. The bodies therefore useful as dies and tools, e.g. cutting tools such as hobs.

Inventors

• 👤 Gary Steven

Bibliographic Details