Method for forming a thermal barrier coating
US6123997A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 15, 1997 |
| Grant date | Sep 26, 2000 |
| Priority date | — |
| Expiry date | Oct 15, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T50/60
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A thermal barrier coating system and a method for forming the coating system which yields a thermal barrier coating having good adhesion to a bond coat overlying a metal superalloy substrate. The adhesion of the bond coat and the thermal barrier coating is enhanced by forming a mature .alpha.-alumina (Al.sub.2 O.sub.3) scale at the bond coat-TBC interface. The desired mature .alpha.-alumina scale can be obtained by utilizing one or more of the following steps: preoxidation of the bond coat at certain minimum temperatures and durations; inoculation of the surface of the bond coat; surface doping or alloying of the bond coat surface; and the addition of noble metals to the bond coat. Each of these steps promotes the formation of .alpha.-alumina and avoids the formation of the .gamma., .delta. and .theta.-alumina phases which undergo phase transformations at elevated temperatures, with the result that a more spallation-resistant thermal barrier coating system is obtained.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.