铝形貌对丁羟推进剂燃速特性的影响

基于丁羟四组元推进剂配方,考察了不同表面形貌的铝(Al)粉对端羟基聚丁二烯(HTPB)推进剂燃速特性的影响,通过扫描电镜(SEM)、激光粒度分布仪分别观察了两种粒度范围在5~10μm的Al粉表面形貌,采用水下声发射法测试了含不同Al粉的HTPB推进剂的燃速,并计算了燃速压强指数。结果表明,Al粉表面形貌可区分为表面附着铝斑粒和表面光滑两种,两种形貌都对HTPB推进剂的燃速特性具有一定的影响。低压段(3~5 MPa),Al粉表面附着铝斑粒时,HTPB推进剂的燃速增幅为1.33 mm·s~(-1),压强指数为0.36;Al粉表面光滑时,HTPB推进剂的燃速增幅为1.29 mm·s~(-1),压强指数为0.34。高压段(12~20 M Pa),Al粉表面附着铝斑粒时,HTPB推进剂的燃速增幅为4.47 mm·s~(-1),压强指数为0.67;Al粉表面光滑时,HTPB推进剂的燃速增幅为2.48 mm·s~(-1),压强指数为0.40。

Effect of Aluminum Morphology on Burning Rate Characteristics of HTPB Propellant

To investigate the effect of aluminum ( Al) powder with different surface morphology on the burning rate of hydroxyl-terminated polybutadiene( HTPB) propellant,based on the formulation of HTPB four component propellant, the morphologys of two kinds of Al (5-10 μm) powder were observed by scanning electron microscopy ( SEM) and laser particle size distribution instrument, and the burning rate of HTPB propellant with different Al powders was measured by underwater acoustic emission method, and the pressure exponent was also calculated.Results show that the surface morphology of Al powder can be distinguished from adhered with Al spot particles and smooth, which have influence on the burning rate of HTPB propellant.At the low pressure stage (3-5 MPa), the burning rate of HTPB propellant increased by 1.33 mm· s-1 and the pressure exponent is 0.36, when the surface morphology of Al powder adhered with Al spot particles.Correspondingly, it is 1.29 mm· s-1 and 0.34, when the surface morphology of Al powder is smooth.At the high pressure stage (12-20 MPa), the burning rate of HTPB propellant increased by 4.47 mm· s-1 and the pressure exponent is 0.67, when the surface morphology of Al powder adhered with Al spot particles, and it is 2.48 mm· s-1 and 0.40, when the surface morphology of Al powder is smooth.