Accession Number:

AD0748266

Title:

Improvement of the Oxidation Resistance of Dispersion Strengthened Nickel-Chromium Alloys.

Descriptive Note:

Final technical rept. 1 Apr 70-30 Sep 71,

Corporate Author:

SHERRITT GORDON MINES LTD FORT SASKATCHEWAN (ALBERTA)

Report Date:

1972-07-01

Pagination or Media Count:

77.0

Abstract:

The cyclic dynamic oxidation and hot corrosion behavior at 2000F 1093C and 2200F 1204C of NiCrThO2 alloys modified by additions of 5 wo aluminum and 0.2 wo yttrium or 3 - 5 wo manganese were measured. Alloys of the composition Ni16-20Cr5Al2ThO2 exhibited the best oxidation resistance having a smaller weight change and less damage by spalling or erosion than the manganese-modified alloys. A thermomechanical procedure was defined to produce a coarse grain microstructure in the aluminum-modified alloys. The procedure consists of primary working by extrusion followed by secondary working by swaging or rolling. The resulting coarse grained alloys have good stress-rupture strength at 2000F 1093C but the ultimate tensile strength is low. A coarse thoria size resulting during processing of the powder through the consolidation step was believed to have contributed to the low tensile strengths at 2000F 1093C. Author

Subject Categories:

  • Properties of Metals and Alloys

Distribution Statement:

APPROVED FOR PUBLIC RELEASE