Patent · US Expired

Differential densification strengthening of glass-ceramics

US3931438A · kind A · utility

198Cited by
10References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 7, 1973
Grant dateJan 6, 1976
Priority date—
Expiry dateNov 7, 1993

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/24992
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A strengthened glass-ceramic laminated article having a compressively-stressed surface layer substantially enveloping a tensilely-stressed core portion, produced by choosing the core and surface layer compositions such that the core undergoes a net positive differential densification with respect to the surface layer as the result of phase transformations occurring in the laminated article during crystallization in situ. Such an article offers significant advantages over glass and glass-ceramic articles strengthened by prior art methods, including improved mechanical stability, thermal shock resistance, and, most importantly, excellent high temperature strength retention.

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