Accession Number:

AD0808520

Title:

DEVELOPMENT OF COATINGS FOR PROTECTION OF DISPERSION STRENGTHENED NICKEL FROM OXIDATION. PART II. DEVELOPMENT OF CR-AL COATINGS BY VACUUM PACK TECHNIQUES.

Descriptive Note:

Final summary rept. 1 Feb-31 Dec 65,

Corporate Author:

DU PONT DE NEMOURS (E I) AND CO WILMINGTON DE PIGMENTS DEPT

Personal Author(s):

Report Date:

1966-03-01

Pagination or Media Count:

112.0

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

Subject Categories:

  • Properties of Metals and Alloys
  • Fabrication Metallurgy

Distribution Statement:

APPROVED FOR PUBLIC RELEASE