Accession Number:

ADA088064

Title:

Dip Process Thermal Barrier Coatings for Superalloys.

Descriptive Note:

Final rept. 1 Jul 79-30 Jun 80,

Corporate Author:

SRI INTERNATIONAL MENLO PARK CA

Report Date:

1980-06-01

Pagination or Media Count:

38.0

Abstract:

A new technique of developing thermal-barrier coatings for superalloys has been investigated. It involves hot dipping of superalloys samples into a molten bath of low melting Ce-Co or Ce-Ni alloy. By internally oxidizing these coatings, it is possible to obtain a duplex with a CeO2-rich oxide scale as the outer layer thermal barrier and in inner layer composite of fine cerium oxide particles dispersed in a matrix of NiCoCrAl. This inner layer, or subscale, grades into the superalloy. Appropriate heat treatment can produce recrystallized CeO2 particles in the subscale that should improve adherence of the oxide scale to the subscale and substrate superalloy. The coating process does involve limited reaction between the coating alloy and superalloy. The thickness of this interaction zone can be controlled and compensated for in the design cross section of the superalloy component. Author

Subject Categories:

  • Coatings, Colorants and Finishes
  • Metallurgy and Metallography

Distribution Statement:

APPROVED FOR PUBLIC RELEASE