Development of Repair and Reprocess Coatings for Air-Cooled Nickel Alloy Turbine Blades.
Abstract
The purpose of this program was to identify, develop and characterize coating compositions, processing techniques and resulting properties for: (1) repair of localized damage to diffused aluminide coatings on nickel base turbine blade alloys and (2) re-application of coatings to worn turbine blades during engine overhaul (reprocess coating). A multiphased effort was undertaken to develop a stripping procedure for removing used aluminide coatings and a coating process for re-applying a new coating as well as for use as a repair. A comprehensive test program was also conducted to compare the environmental performance of reprocess and repair coatings and to evaluate the effects of the new coatings on the mechanical properties of the substrate relative to the corresponding properties of the original coatings. A chemical stripping procedure was developed for removing remnant Jo-Coat from B-1900 and INCO-713C and CODEP C-2 from IN-100 and U-500 without significant substrate attack. Grit blasting was found to be satisfactory for partial stripping wherein only surface scale and oxides required removal. A vacuum fired slurry slip pack coating process using 56Cr-44A1 powder as a source material was developed which was capable of affecting both complete recoatings as well as repair coatings to locally damaged areas.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1971
- Accession Number
- AD0892786
Entities
People
- E. E. Jones
- J. V. Peck