NONSTEADY-STATE THERMAL STRESS BEHAVIOR OF REFRACTORY MATERIALS.

Abstract

The thermal and deformation histories of hollow cylindrical specimens were measured during exposure to high heat fluxes produced by electron bombardment of the inside surfaces of the specimens. Transient thermal environments comparable in severity to those produced by rocket engine exhaust and re-entry heating were considered. Using the measured thermal history as input to a thermal stress analysis stresses and strains throughout the specimen were calculated. Plasticity and anisotropy are taken into account in the analysis. Good correlation was obtained for values of measured and calculated circumferential strains for the outside diameter of the specimens. Results were obtained for AXF-5Q, AXF-9Q, PO-3 and ATJ graphite and recrystallized extruded tungsten. High temperature mechanical properties were measured in using special test apparatus and procedures which were developed to meet the requirements of the thermal stress analysis. Results for tungsten at temperatures up to 5500 F and for strain rates of 0.1 to 10 in./in./min. were presented. A parametric study was conducted to obtain a better understanding of the thermomechanical behavior of cylindrical bodies subjected to large transient temperature and pressure loadings. The parameters were evaluated in terms of the influence they exert on the stresses and strains induced at the inner and outer surfaces of the cylinder. (Author)

Document Details

Document Type
Technical Report
Publication Date
Nov 01, 1967
Accession Number
AD0823487

Entities

People

  • Charles H. Ernst
  • Jack R. Bohn
  • Kenneth R. Janowski
  • Kenneth R. King

Organizations

  • TRW Inc.

Tags

DTIC Thesaurus Topics

  • Cylindrical Bodies
  • Graphitic Materials
  • Heat Flux
  • Heat Resistant Materials
  • High Temperature
  • Materials
  • Mechanical Properties
  • Plastic Properties
  • Refractory Materials
  • Rocket Engines
  • Strain Rate
  • Stress Analysis
  • Stresses
  • Thermal Stresses
  • Tungsten

Readers

  • Combustion and Flow Dynamics.
  • Materials Science (Mechanical Engineering).
  • Plasma Physics.

Technology Areas

  • Microelectronics