Accession Number : AD0657024

Title :   DEVELOPMENT OF HIGH TEMPERATURE THERMAL CONDUCTIVITY STANDARDS,

Descriptive Note : Technical rept. 3 May 65-3 Nov 66,

Corporate Author : LITTLE (ARTHUR D) INC CAMBRIDGE MASS

Personal Author(s) : Wechsler,Alfred E.

Report Date : JAN 1967

Pagination or Media Count : 143

Abstract : An analytical and experimental study was proposed to establish high temperature thermal conductivity and diffusivity standards and to test these standards. The report describes the identification, selection, characterization and preliminary experimental examination of candidate standard materials for use in the subsequent measurement program. Based on criteria such as phase change, melting point, reproducibility, isotropy, fabricability, homogeneity, and availability, the following materials were selected for experimental evaluation: ceramics--alumina, beryllia, thoria, calcium zirconate, and yttria-stabilized zirconia; intermetallics--silicon carbide, boron carbide, titanium carbide, and zirconium diboride; metals--molybdenum, tantalum, tungsten, tantalum-10% tungsten, and molybdenum-30% tungsten; graphites--ATJ, CEQ, RVD, PO-3, DS-13, 1924-H, 7890, XUT-31, and UF4S. Samples of these materials were obtained in sizes similar to those used in thermal conductivity and diffusivity apparatus. The experimental evaluation consisted of visual examination, density measurements, microstructural examination, heating tests simulating the environment and temperature cycling encountered in thermal property measurements, preliminary thermal conductivity measurements, and preliminary electrical resistivity measurements. Based upon the experimental results, aluminum oxide, thorium oxide, arc cast tungsten, and grades 1924-H (or AXM-5Q1) and RVD graphites were selected for the Phase II measurements program. (Author)

Descriptors :   (*THERMAL CONDUCTIVITY, STANDARDS), CERAMIC MATERIALS, METALS, INTERMETALLIC COMPOUNDS, GRAPHITE, THERMAL DIFFUSION, PHASE STUDIES, MECHANICAL PROPERTIES, HIGH TEMPERATURE, TUNGSTEN, OXIDES

Subject Categories : Physical Chemistry
      Ceramics, Refractories and Glass
      Properties of Metals and Alloys
      Thermodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE