DEVELOPMENT OF COATINGS FOR PROTECTION OF DISPERSION STRENGTHENED NICKEL FROM OXIDATION. PART II. DEVELOPMENT OF CR-AL COATINGS BY VACUUM PACK TECHNIQUES.
Abstract
A program was conducted to develop vacuum pack processing parameters for reproducibly forming the duplex Cr-Al coating system on TD Nickel. Target protective capabilities of 500 hours cyclic oxidation protection at 2200 F and 100 hours protection at 2400 F were achieved and demonstrated with the vacuum pack Cr-Al coating. Data are presented detailing the parameters required to form the Cr-Al coating on TD Nickel by the vacuum pack process. Parametric studies were conducted in both laboratory size (3 in diameter x 8 in retort) and pilot scale (8 in diameter x 20 in retort) coating furances. A spray-diffusion technique was also developed for formation of the duplex Cr-Al coating on TD Nickel. The analogous microstructures of the spray and pack formed Cr-Al coatings are shown pictorially; and the spray processing parameters are discussed in detail. At the conclusion of the program an evaluation study was conducted to comparatively characterize the properties of uncoated and Cr-Al coated TD Nickel. The evaluation tests included: (1) cyclic oxidation in moving air at 1600, 2000, 2200 and 2400 F, (2) thermal shock tests (oxy-acetylene) at peak temperatures of 2200 and 2400 F, (3) tensile tests at temperatures from RT to 2400 F, and (4) stress-oxidation tests at 2200 and 2400 F. The evaluation data, presented pictorially and graphically, are discussed in detail. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1966
- Accession Number
- AD0808520
Entities
People
- J. D. Gadd