Patent · US Expired

Method for clad-coating ceramic particles

US5184662A · kind A · utility

27Cited by
3References
6Claims
0Family size

Inventors

Key dates

Filing dateAug 6, 1991
Grant dateFeb 9, 1993
Priority date
Expiry dateAug 6, 2011

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB22F2998/10
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

Metal and ceramic particles of various morphologies are clad with a coating from the transistion metal group consisting of silver, gold, copper, nickel, iron, cobalt, aluminum etc., or combinations thereof, to provide improved coated particles for microelectronics or metal matrix composites or other uses. Refractory metal precursor core particles, such as tungsten, molybdenum, niobium and zirconium, as examples, are provided from a composite of tungsten and copper, for example, made by pressurizing and infiltrating or liquid phase sintering of molten copper into a porous tungsten skeleton. Precursor chip particles derived from a tungsten impregnated billet are used as starter particles which may be further enhanced by cogrinding in an attritor ball mill with smaller copper particles to thereby produce an enhanced copper clad-coating of tungsten particles with predetermined percent by weight of copper and tungsten content. The resulting particles exhibit improved electrical and thermal expansion coefficient matching properties for use on microelectronic ceramic substrates and when used for metal matrix composites, provides more uniform distribution of the dispersed strengthening par…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.