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)

Personal Author(s) : Timbres,Donald H. ; Norris,L. Fredrick ; Clegg,Maurice A.

Report Date : JUL 1972

Pagination or Media Count : 77

Abstract : The cyclic dynamic oxidation and hot corrosion behavior at 2000F (1093C) and 2200F (1204C) of Ni/Cr/ThO2 alloys modified by additions of 5 w/o aluminum and 0.2 w/o yttrium or 3 - 5 w/o manganese were measured. Alloys of the composition Ni/16-20Cr/5Al/2ThO2 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)

Descriptors :   (*NICKEL ALLOYS, CORROSION RESISTANCE), HEAT RESISTANT ALLOYS, HEAT RESISTANT METALS, CHROMIUM ALLOYS, DISPERSION HARDENING, ALUMINUM ALLOYS, MECHANICAL WORKING, CORROSION INHIBITION, CANADA

Subject Categories : Properties of Metals and Alloys

Distribution Statement : APPROVED FOR PUBLIC RELEASE