THE HIGH-TEMPERATURE STABILITY OF THORIA-STRENGTHENED NICKEL-CHROMIUM ALLOYS.

Abstract

Two nickel-base, 20% chromium - 2% thoria alloys, manufactured by different techniques, were studied with regard to their response to high-temperature exposure. Both alloys retained their dislocation substructure after 1-hr annealing treatments up to 1800F. Annealing above this temperature resulted in a decrease in room temperature hardness of one of the alloys, while the other retained its original hardness and remained microstructurally stable up to 2400F. The decrease in hardness was associated with a decrease in the dislocation density and an increase in grain size. The thoria particles in the stable alloy had an average diameter of 550 A, as compared to 820 A for the less stable alloy. It appears that the difference in the particle sizes accounts for the difference in the structural stability at elevated temperatures. (Author)

Document Details

Document Type
Technical Report
Publication Date
Dec 23, 1968
Accession Number
AD0680389

Entities

People

  • Joachim P. Neumann
  • Louis Raymond

Organizations

  • The Aerospace Corporation

Tags

DTIC Thesaurus Topics

  • Alloys
  • Annealing
  • Chromium
  • Chromium Alloys
  • Diameters
  • Dislocations
  • Grain Size
  • Hardness
  • High Temperature
  • Particle Size
  • Particles
  • Physical Properties

Fields of Study

  • Materials science

Readers

  • Powder metallurgy of Titanium alloys.