Patent · US Expired

Process of hot isostatic pressing of ferrite material

US4552710A · kind A · utility

4Cited by
9References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 3, 1984
Grant dateNov 12, 1985
Priority date
Expiry dateJan 3, 2004

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC04B35/6455
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

Process of hot isostatic pressing of MnZn ferrite material for producing ferrite close to theoretical density without a significant increase in grain size. Permeability is increased with the increase in theoretical density. The process includes the steps of pressurizing an entire ferrite sample which is surrounded by pieces of similar composition while in alumina crucibles with fused alumina grain there between and an optional oxygen getter on top of the grain, introducing an inert atmosphere, elevating pressure and temperature, the temperature elevated to a value below that previously used for sintering or hot pressing, and maintaining temperature to optimize density without excess grain growth. Density is thereby optimized without excess grain growth, while maintaining or improving the magnetic properties.

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