Effect of iron oxide on the combustion of condensed mixtures

Abstract

We have invest igated the effect of-l% FezO 3 on the burning rate of model mixtures of ammonium perchlorate (AP) + polystyrene (PS) and ammonium perchlorate + po lymethyl methacry la te (PMM) when var i ous physical parameters are varied (pressure, component ra t io a, in i t im temperature T 0, presence of inert diluents--NH4C1 and AlzOa). The effect ive par t ic le sizes were approximate ly 9 p for AP ( technical), 5 g for PS (technical) , 3 g for PMM (technical) , 1 .8 g for Fe203 (ana ly t ica l grade), 12 # for NH4C1 (ana ly t ica l grade), and 8 p for AlzOs (ana ly t ica l grade). The components were mixed on t racing cIoth with a rubber stopper for one hour. From the finished mixture we pressed charges 8 mm in d iameter and 8 -10 mm ta l l with a re la t ive density 6 = P/Pmax = 0 .950.99. The exper iments were conducted in a constant-pressure bomb in nitrogen. The burning t i m e w was measured using a quartz pressure transducer. The average burning rate u = h / r was ca lcula ted . We charac ter ize the effect ol~ the Fe2Os by means of the quant i ty z = u/n0, where u and u0 are the burning rates of the mixture with and without the addit ion of FezOa.