MICROSTRUCTURE STUDIES OF POLYCRYSTALLINE REFRACTORY OXIDES.

Abstract

The elastic modulus and transverse bend strength of pure, dense alumina and magnesia specimens were determined as a function of grain size (1 to 250 microns) and temperature over the range of 30 to 1500 C. The elastic modulus of both com pounds was found to be essentially independent of grain size over the temperature range covered. The transverse bend strength of fine-grain-size alumina was found to be substantially greater than larger-grain-size alumina over the entire temperature range although, at the highest temperatures, the rate of decrease of strength with temperature was greatest for the fine-grain material. The transverse bend strength of magnesia was less dependent on grain size than the alumina; and, in addition, this dependence showed further decreases with temperature. At higher temperatures, the larger-grain-size speci mens exhibited greater strengths than the fine grain magnesia. (Author)

Document Details

Document Type
Technical Report
Publication Date
Aug 07, 1963
Accession Number
AD0413994

Entities

People

  • J.b. Mitchell
  • R.m. Spriggs
  • T. Vasilos

Tags

DTIC Thesaurus Topics

  • Grain Size
  • Materials
  • Microstructure
  • Modulus Of Elasticity
  • Physical Properties
  • Polycrystals
  • Transverse

Fields of Study

  • Materials science

Readers

  • Powder metallurgy of Titanium alloys.
  • Reinforced Composite Materials