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:
Mar. 07, 1989
Filed:
Apr. 04, 1988
Norman S Hoyer, Mt. Lebanon, PA (US);
Natraj C Iyer, Monroeville, PA (US);
Westinghouse Electric Corp., Pittsburgh, PA (US);
Abstract
A process of hot isostatic pressing of powders to form electrical contacts is characterized by the steps: (A) mixing powders, 1 in the Drawing, from metal containing powder or metal containing powder plus carbon powder, where at least one of Ag and Cu is present, (B) thermal cleaning treatment of the powder, 2 in the Drawing, (C) granulating the thermally treated powder, 3 in the Drawing, (D) uniaxially pressing the powders without heating, 5 in the Drawing, to provide a compact, (E) placing at least one compact in a pressure-transmitting, pressure-deformable container, 6 in the Drawing, and surrounding each compact with fine particles of a separating material, (F) evacuating air from the container, 7 in the Drawing, (G) sealing the compacts inside the container, 8 in the Drawing, (H) hot isostatic pressing, 9 in the Drawing, the compacts through the pressure transmitting material at a pressure from 352 kg/cm.sup.2 to 2,115 kg/cm.sup.2 and a temperature from 0.5.degree. C. to 100.degree. C. below the melting point of the lower melting powder constituent, to provide simultaneous hot-pressing and densification of the compacts, (I) gradually cooling and releasing the pressure on compacts, 10 in the Drawing, and (J) separating the compacts from the container, 11 in the Drawing, where there is no heating of the compacts in the process before step (H).