铝水推进剂用高活性铝基燃料制备及水解性能研究

Study on preparation and hydrolysis properties of high active Al-based composite used in Al-H_2O propellant

采用机械球磨法制备了一系列高活性铝基燃料,并通过XRD、SEM和水解性能测试考察了盐和氢化物掺杂对铝合金性能的影响。结果表明,氢化物(盐)的加入明显改善了铝合金水解性能。以Al-10%Bi-10%MgH2合金水解为例,1 g该合金水解产生783 ml/g氢气(不包含0.1 g的MgH2水解产生的167 ml氢气),氢气生成速率为78.3 ml/(min.g),远远超过Al-16%Bi合金氢气产量(670 ml/g)和氢气生成速率(23 ml/(min.g))。氢化物(盐)的作用在于:(1)在球磨过程中,氢化物(盐)有利于减小铝基燃料的粒径;(2)氢化物(盐)溶解产生的热量有利于改善铝基燃料的水解动力学;(3)氢化物(盐)溶解产生大量的导电性离子,促进了铝基燃料在水中迅速形成微型腐蚀电池,并加快微型腐蚀电池工作。

The Al-based composites were prepared via milling method, and the effects of hydride（ salts）on their performances were studied through the measures of XRD, SEM and hydrolysis. The results show that the additive hydrides （salts） have improved the hydrolysis performances of the Al-based composites. For example, Al-10% Bi-10% MgH2 has much higher hydrolysis properties （783 ml/g hydrogen（not including 167 ml hydrogen from the hydrolysis of 0.1 g MgH：） and 78.3 ml/（min · g） ）than that of Al- 16% Bi alloy（670 ml/g and 23 ml/（ min ·g） ）. The improved hydrolysis performance comes from the following factors： （ 1 ）The ad- ditive hydrides（salts） favors decreasing the particle sizes of the Al-based composites in the milling process;（2）The dissolution enthalpy improves the hydrolysis kinetics of Al-based composites ; （ 3 ） A quantity of ions produced from hydrides （salts） solution quickens the work of the micro-galvanic cell between Al and other metals.