STUDY OF THERMAL AND MECHANICAL PROPERTIES OF SELECTED SOLIDS FROM 4 DEGREES TO THE MELTING POINT.

Abstract

The theory of thermal expansion is briefly reviewed with special emphasis on the negative low temperature expansion frequently found in the diamond and sphalerite crystal structures. Lattice parameters of the rock salt compounds AgCl, AgBr and MgO, and the sphalerite compounds CuCl, CuBr, CuI, AgI, BN, BP, SiC, and CdTe measured from 4.2K to 300K are presented. The rock salt compounds are found to behave normally, i.e., positive throughout the temperature range. CuCl, CuBr, AgI, CdTe, and probably BN and BP possess a region of low temperature negative expansion. Within the limits of experimental error, CuI and SiC do not. The thermal expansion of AgI is found to be dependent on its preparation; this has been attributed to the presence of stacking faults. (Author)

Document Details

Document Type
Technical Report
Publication Date
Nov 15, 1969
Accession Number
AD0699579

Entities

People

  • Herbert F. Schaake

Organizations

  • Martin Marietta

Tags

DTIC Thesaurus Topics

  • Crystal Structure
  • Crystals
  • Isothermal Processes
  • Low Temperature
  • Mechanical Properties
  • Melting
  • Melting Point
  • Phase Transformations
  • Thermal Expansion

Fields of Study

  • Materials science

Readers

  • Materials Science and Engineering.