Abstract: A process for making a workpiece suitable for being hot worked to produce a wrought metal poduct is described. Aluminum alloy powder is cold compacted and then heated in an inert environment to provide a sinter-sealed shape. The resultant workpiece may then be subjected to conventional processing to produce the desired wrought product.
Abstract: Article produced in a mould for a plastics moulding tool having a mould surface defining the contours of the article, with the article comprising a body formed from a composition comprising a sinterable material having a sintering temperature which material, before sintering, is shapable into a desired shape and which during sintering forms a porous body having pores, the sinterable material being at least partially sintered in the mould, and also comprising a matrix having a lower melting point than the sintering temperature of the sinterable material, with the matrix comprising a matrix metal which is infiltrated in the porous body to substantially fill the pores.
Abstract: A method of preparing electrical contacts and electrical contact materials comprises the steps of blending a conductive metallic component, such as silver, with nickel and zirconium diboride which is substantially completely free of oxides, pressing the powder mixture to form a pre-sintered compact, and thereafter liquid phase sintering the compact to a densified body.The zirconium diboride is mixed with about 2 weight percent of a reducing agent, preferably mixed carbon and boron powders, and heated to remove oxides from the surface of the zirconium diboride powder particles prior to the steps of pressing and sintering.
Type:
Grant
Filed:
January 4, 1982
Date of Patent:
May 22, 1984
Assignee:
GTE Laboratories Incorporated
Inventors:
Thomas E. Peters, John C. Gustafson, Boon Wong
Abstract: A method of the preparation of an improved high-density sintered alloy composed mainly or iron and up to 50 wt. % of copper, in which boron is added in an amount of no less than 0.03% to suppress or limit the copper growth phenomenon during sintering. The alloys prepared by the present method undergo less dimensional changes during sintering and are thus of a very high density as compared with the conventional alloys of the same type.
Abstract: The present invention discloses a method for densifying previously sintered parts constructed of powdered metals, ceramics or the like to nearly 100% theoretical density. The method of the present invention comprises heating the parts above their liquid phase temperature and then applying a pressure in the range of 50-2,000 psi to the parts for a predetermined period of time and simultaneously maintaining the parts at or above their liquid phase temperature. The method of the present invention achieves complete closure of even large voids and the elimination of substantially all porosity within the part.
Abstract: In the preferred embodiment, a method is presented for forming an iron-base article by powder metallurgy, which includes compacting a powder mixture comprising a major portion of iron particles and between about 2 to about 5 weight percent of a powder consisting of hypereutectic tricopper phosphide Cu.sub.3 P compound. The compact is sintered at a temperature between about 970.degree. C. to about 1100.degree. C., whereupon the copper phosphide forms a liquid that flows and wets the iron particle surfaces. During sintering, phosphorus from the copper phosphide diffuses into the iron particles and resulting copper-enriched liquid forms a film coating pore surfaces in the compact. The sintered article displays an improved combination of ductility and strength, particularly in view of the relatively low sintering temperature.
Abstract: The present invention is directed to a process for preparing a body of polycrystalline silicon doped with aluminum comprising melting a mixture of silicon powder and aluminum powder, rapidly quenching the melt, grinding the solidified silicon-aluminum alloy and hot pressing to form a compact.
Abstract: A compound substance of great hardness and toughness, comprising a metal matrix, having embedded therein, hard material granules of a size of 0.1 to 5 mm. The metal matrix comprises 1 to 4% carbon, 0.3 to 0.6% silicon, 0.5 to 1.5% manganese, 0.8 to 2.8% vanadium, 0.5 to 1.5% chromium, 2 to 10% tungsten, about 0.01% aluminum and the remainder, iron.
Type:
Grant
Filed:
May 7, 1980
Date of Patent:
December 28, 1982
Assignee:
Fried. Krupp Gesellschaft mit beschrankter Haftung