Accession Number : ADA308610

Title :   Torsion Pendulum Measurements on Viscoelastic Materials During Vacuum Exposure.

Descriptive Note : Contractor rept.,

Corporate Author : VIRGINIA POLYTECHNIC INST AND STATE UNIV BLACKSBURG

Personal Author(s) : Ward, Thomas C. ; Evans, Morris L.

PDF Url : ADA308610

Report Date : JUN 1972

Pagination or Media Count : 73

Abstract : A torsional pendulum apparatus designed for testing in situ in vacuum, the dynamic mechanical properties of materials is described. The application of this apparatus to an experimental program to measure the effects of vacuum (0.00001 torr) on the mechanical properties of two ablator materials (a foamed material and a filled elastomer) and a solid rocket propellant (a filled elastomer) is presented. Results from the program are discussed as to the effects of vacuum on the mechanical properties of these three materials. In addition, time-temperature-superposition, as a technique for accelerating vacuum induced changes in mechanical properties, is discussed with reference to the three materials tested in the subject program.

Descriptors :   *VISCOELASTICITY, *SOLID ROCKET PROPELLANTS, *ABLATIVE MATERIALS, STRESS STRAIN RELATIONS, PRESSURE GRADIENTS, TIME DEPENDENCE, EXPOSURE(GENERAL), POLYMERS, ACCELERATION, HIGH TEMPERATURE, TENSILE STRESS, MODULUS OF ELASTICITY, VACUUM, ELASTOMERS, MOISTURE CONTENT, TEMPERATURE GRADIENTS, ERROR ANALYSIS, HEAT SHIELDS, BINDERS, POLYURETHANE RESINS, ACCELERATED TESTING, HUMIDITY, TORSION, FOAM, FILLERS.

Subject Categories : Mechanics
      Solid Rocket Propellants
      Plastics

Distribution Statement : APPROVED FOR PUBLIC RELEASE