In-situ formed thermal barrier coating for a ceramic component
US7402347B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 7, 2005 |
| Grant date | Jul 22, 2008 |
| Priority date | — |
| Expiry date | May 9, 2025 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF05D2300/614
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A thermal barrier layer (20) is formed by exposing an oxide ceramic material to a thermal regiment to create a surface heat affected zone effective to protect an underlying structural layer (18) of the material. The heat affected surface layer exhibits a lower strength and higher thermal conductivity than the underlying load-carrying material; however, it retains a sufficiently low thermal conductivity to function as an effective thermal barrier coating. Importantly, because the degraded material retains the same composition and thermal expansion characteristics as the underlying material, the thermal barrier layer remains integrally connected in graded fashion with the underlying material without an interface boundary there between. This invention is particularly advantageous when embodied in an apparatus formed of an oxide-oxide ceramic matrix composite (CMC) material wherein reinforcing fibers (24) are anchored in the underlying load-carrying portion and extend into the non-structural thermal barrier portion to provide support and to function as surface crack arrestors. In one embodiment an airfoil (10) is formed of a stacked plurality of CMC plates having such a heat-affected t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.