Accession Number : ADA181254

Title :   Aging and Surveillance Program Minuteman II/III Stage II Program Progress.

Descriptive Note : Rept. for 1 Sep 86-15 Mar 87.

Corporate Author : AEROJET STRATEGIC PROPULSION CO SACRAMENTO CA

Report Date : MAY 1987

Pagination or Media Count : 233

Abstract : Statistically significant correlations, relationships and trends have been developed throughout the aging program which can be applied to service life assessment. Measurement of moisture within sealed rocket motors indicates that moisture equilibrium in the bore is reached in approx. 2 years. Average moisture following equilibrium was approx. 15% RH measured at 80 F (or 21% RH measured at 70 F). A total of 13 full-scale motors which were weather sealed at time of manufacture have been measured for moisture content. Motors ranged in age from 3.6 to 77..6 months at time of test. Testing of plug samples removed from 3 motors indicates considerable variation in propellant and properties within given motor due to propellant batch-to-batch variation. With aging, propellant properties indicate continued hardening to 36 months. Bond properties are generally unchanged in the chamber area with aging, but variation among motors tends to be large. Bond strength in the aft ends of all motors is decreased with age, expected based on testing of approx. 130 excise samples. Gradients in mechanical and chemical properties were measured as a function of distance from the bondline interface. For plug samples removed from Motors MSEX-2 and R7-032, data indicate higher modulus and crosslink density (and correspondingly lower strain capability) adjacent to the bondline (0.1 in.) than at distances greater than 1. in. Propellant strength is not affected by proximity to the bondline.

Descriptors :   *AGING(MATERIALS), *SOLID ROCKET PROPELLANTS, *SECOND STAGE ENGINES, TEST METHODS, STRENGTH(MECHANICS), CROSSLINKING(CHEMISTRY), DENSITY, CHEMICAL PROPERTIES, MECHANICAL PROPERTIES, EQUILIBRIUM(GENERAL), MOISTURE, BONDING, CHAMBERS, MEASUREMENT, MOISTURE CONTENT, PLUGS, SAMPLING, ROCKET ENGINES, SEALED SYSTEMS, TIME, STRENGTH(GENERAL), LIFE EXPECTANCY(SERVICE LIFE), HARDENING, VARIATIONS, LININGS, GRADIENTS, STRAIN(MECHANICS), CORRELATION, WEATHERPROOFING, SURFACE TO SURFACE MISSILES, SURVEILLANCE

Subject Categories : Solid Rocket Propellants
      Solid Propellant Rocket Engines

Distribution Statement : APPROVED FOR PUBLIC RELEASE