Accession Number : AD0868196

Title :   Validation of Crack Propagation Analytical Techniques.

Descriptive Note : Rept. on D-3 test performance.

Corporate Author : GENERAL ELECTRIC CO PHILADELPHIA PA RE-ENTRY SYSTEMS DEPT

Report Date : 31 MAR 1970

Pagination or Media Count : 113

Abstract : The D-3 Test was aimed at empirically investigating crack growth of curved cracks in rings to validate or indicate required modifications to fracture mechanics techniques for frustum analyses, and this has been accomplished. The program consisted of mechanical testing of isotropic - ATJ and polymethyl methacrylate (PMM) - tee section rings with thin machined cracks to where crack growth was forced to occur, and thermally loading composite carbon phenolic/epon/steel cylinders in an oxy-hydrogen torch facility to generate thermal stresses representative of re-entry conditions. Cracks were formed in the composite cylinders both by using teflon inserts to prevent bonding between the bond and heatshield over desired ranges, and by damaging the cylinders with sheet explosives. The latter technique produces damage more representative of encounter induced damage.

Descriptors :   (*REENTRY VEHICLES, CRACK PROPAGATION), (*GUIDED MISSILE WARHEADS, DAMAGE ASSESSMENT), FRACTURE(MECHANICS), NOSE CONES, CRACKS, AERODYNAMIC LOADING, RINGS, HYDROGEN, TORCHES, OXYGEN, TEST METHODS, HEATING, HEAT SHIELDS, HEAT FLUX, COMPOSITE MATERIALS, LOADS(FORCES), SPALLATION, AERODYNAMIC HEATING, ATMOSPHERE ENTRY, SIMULATION, THERMAL STRESSES, ACRYLIC RESINS, PHENOLIC PLASTICS, CARBON, GRAPHITE, STEEL, STRAIN(MECHANICS).

Subject Categories : Guided Missile Reentry Vehicles
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE