MANUFACTURING METHODS FOR HIGH TEMPERATURE COATING OF LARGE COLUMBIUM PARTS
Abstract
A program was conducted to develop a manufacturing method for producing the high temperature oxidation resistant Cr-Ti-Si coating on large columbium parts. The program was accomplished in three principle development areas: (1) scale-up of the diffusion pack process for producing the Cr-Ti-Si coatings, (2) scale-up of the slurry diffusion process for producing this coating, and (3) production proof of the slurry diffusion process. A vacuum furnace with hearth dimensions of 42 in. diameter x 48 in. high was constructed and successfully adapted to application of the Cr-Ti-Si coating. Cr-Ti-Si coatings formed in the production-scale furnace by both the vacuum pack and slurry-diffusion methods reliably protected columbium alloys from oxidation for times greater than 125 hours at 1800 deg F and 50 hours at 2600 deg F. Three secondary areas of investigation were also undertaken: (1) an investigation of the effects of edge preparation and edge radius on the protection offered by the Cr-Ti-Si coating system, (2) a development using fused silicides, locally applied and fired either in argon or air, for repairing defects in unoxidized and oxidized coatings, and (3) an evaluation of the effect of the Cr-Ti-Si coatings system on the tensile properties of 0.018 inch Cb752 alloy sheet.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1968
- Accession Number
- AD0835378
Entities
People
- Herbert A. Fisch
- John D. Gadd