Rapid tooling sintering method and compositions therefor

Abstract

A rapid tooling method is provided for molding metal particles, ceramic particles or mixtures thereof directly from patterns comprising a meltable, soluble or decomposable substance and preferably formed by rapid prototyping technology, as well as particle compositions therefor. The method comprises mixing at least about 95% by weight sinterable metal particles, sinterable ceramic particles or mixtures thereof with at least about 0.5 wt. % to about 5.0 wt. % binder to form a powder mixture; casting the mixture around a pattern; applying pressure sufficient to compact the mixture to form a preform; removing the pattern; and heating the preform at a sintering temperature sufficient to sinter the particles and form a molded article. The pattern may be removed by either melting, dissolving or decomposing, and the sintering process preferably includes two stages which are performed simultaneously with the infiltration of metal, whereby which both shrinkage and distortion of molded article can be reduced or eliminated.

Dependencies are inferred from the claim text.