This paper presents the results of an experimental study of the combustion of composite solid propellants with a double oxidizer (ammonium perchlorate/HMX) at pressures of 0.03-0.1 MPa. Systems containing a micron-sized aluminum powder (ASD-4) and the Alex ultrafine aluminum powder were investigated. It was shown that the replacement of ASD-4 by Alex in propellant systems led to an increase in the burning rate. The aluminum particle size and the oxidizer excess coefficient were found to affect the exponent in the power-law burning-rate dependence. The range of the oxidizer excess coefficient was determined that corresponded to the effective replacement of micron-sized aluminum by ultrafine aluminum for which the exponent in the power-law burning rate dependence decreases.Key words: composite solid propellant, subatmospheric pressure, ultrafine aluminum powder, ammonium perchlorate, HMX, burning-rate law.

Experimental results on the stationary burning rate and solid content in the combustion products of mixed compositions with a chlorine-free oxidizer and an active fuel binder in the pressure range 0.025-6.0 MPa are presented. The effect of catalytic additives (silica and carbon black), the particle size of aluminum powder, and the method of preparing samples for combustion of the mixed compositions under consideration are analyzed.

Abstract. This paper presents the results of an experimental study of the high-energy materials combustion at subatmospheric pressures. Systems containing powders of micron-sized aluminum, ultrafine aluminum, boron and their mechanical mixtures were investigated. Effect of the replacement of aluminum by aluminum-boron mixtures in propellant systems on the burning rate law was determined.Keywords: aluminum, boron, powder dispersity, subatmospheric pressure, burning rate law. 1.IntroductionOne of main component of high-energy materials (HEMs) is a metal fuel. The traditional metal fuel is aluminum, whose influence on the HEMs burning rate was studied in a wide range of pressures in various active media for powders of different dispersion [1][2][3].This work presents the results of thermodynamic calculation, the characteristics of the products of combustion of high-energy materials containing a mixture of aluminum-boron, and the results of measurements of the burning rate of compositions in subatmospheric pressure. In the experiment ranged various binder dispersity of aluminum powder and composition of the metal fuel.We studied HEMs compositions based on ammonium perchlorate (AP) and organic fuel (SKDM-80), containing 15 wt % metal powders (micron-size aluminum ASD-4, ultrafine aluminum Alex, boron and their mechanical mixtures). Table 1 shows the density ρ, dispersity, enthalpy of formation ΔH and the equivalent formulas HEMs components [4]. Characteristics of studied HEMs compositions are presented in the table 2. The oxidizer excess coeƥcient for these compositions was α=0.5.

Der Indolylacrylsäureester (I) reagiert mit NOCl in siedendem Benzol zu einem Gemisch der Ester (II) und (III).