Thermo-Mechanical Analysis of Homo- and Heterogeneous Solid Rocket Propellants

摘要

The paper analyses results of experimental research of homogeneous and heterogeneous solid rocket propellants. The homogeneous sample PAC with density 1.58 g/cm~3 and heterogeneous sample H2 with density 1.77 g/cm~3 were both subjected to complex thermo-mechanical analysis. The thermo-physical properties of both samples were determined using KD2 Pro apparatus made by Decagon Devices, Inc. (USA). The temperature characteristics of thermal conductivity λ(T), thermal diffusivity a(T), and volumetric heat capacity C=ρ·c_p(T) were measured within the temperature range from -20°C to +80°C. Mechanical properties such as storage modulus (E'), loss modulus (E") and tan(delta) were measured using Netzsch DMA 242C analyser within temperature range from -120°C to +80°C at heating rate of 2 K/min. The rectangular test samples were subjected to the dual cantilever mode with frequency f = 1Hz recommended by the NATO 4540 standard. Special attention was devoted to determining the glass transition temperature and softening temperature of the propellants. The temperature values obtained during DMA experiments supported by thermo-physical properties are essential for safe usage of solid rocket propellants under operating conditions and they may be applied in numerical modeling of temperature and thermal stress distributions of such materials.