Patent · US Expired

Alumina abrasive grains and method for manufacturing the same

US4252544A · kind A · utility

129Cited by
3References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 9, 1979
Grant dateFeb 24, 1981
Priority date
Expiry dateMay 9, 1999

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC09K3/1436
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

Alumina abrasive grains having a density of more than 3.75 g/cm.sup.3 and a hardness (Knoop) higher than 1,900 Kg/mm.sup.2 are disclosed as useful in manufacturing a grinding wheel with which sharp grinding is carried out under heavy loads. The grains are characterized in that the grain structure thereof is constructed of electrofused or high temperature calcined alumina coarse crystal particles and alumina fine crystal particles which are located between said alumina coarse crystal particles, the latter having particle sizes smaller than that of the former and being processed at a calcination temperature lower than that of the former, wherein said fine crystal particles are sintered integrally with said coarse crystal particles. The method of making the grains is also disclosed.

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