The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 29, 2003
Filed:
May. 26, 1998
Gongyao Zhou, Cherry Hill, NJ (US);
Zongyan He, Philadelphia, PA (US);
Drexel University, Philadelphia, PA (US);
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.