Use of Dynamic Mechanical Measurements to determine the aging behavior of solid propellant

Abstract

Abstract A process for determining the aging characteristics of solid rocket propellants by measuring their dynamic mechanical properties is described. Samples of rocket propellant are tested using a mechanical spectrometer at low strain levels and low frequencies. The change in the dynamic storage modulus of the propellant with aging time and temperature is used to determine the aging rate anf the likely mechanisms occuring during aging. The technique is advantageous is several respects: because the tests are non‐destructive and use small test specimens, and entire aging program can be conducted using much less propellant than is required ihn traditional aging programs (propellant requirements are reduced by more than an order of magnitude) the technique can be applied to samples with unusual or unique geometries which cannot be tested using traditional methods; test specimens can be obtained directly from live, operational solid rocket motors, and service life and mechanical property degradation can be determined.