Ceramic bodies having a plurality of stress zones
US4876148A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 30, 1987 |
| Grant date | Oct 24, 1989 |
| Priority date | — |
| Expiry date | Jun 30, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2973
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Ceramic bodies having a balanced overall stress pattern in which are present individual stress zones of compressive and tensile stresses and the techniques for forming said bodies are disclosed. The bodies are formed by having slightly different compositional patterns from one zone to another whereby during cooling there is a differential volumetric expansion or contraction in one zone as compared to an adjacent zone. The volumetric expansion or contraction is caused by a material which undergoes a phase transformation during the cooling from the sintering temperatures utilized to sinter the ceramic body, whereby such phase transformation is accompanied by a volumetric change.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.