Aluminum (Al)/lithium (Li)-alloy-based fuels can potentially improve composite propellant performance and reduce hydrochloric acid formation. Shattering microexplosions have been observed in Al–Li-based composite propellants at 0.1 MPa; however, combustion characterization of Al–Li-based propellant as a function of pressure has not been performed previously. Measurement of the burning rate of an Al–Li composite propellant and quantification of agglomerate production near the propellant surface at various pressures are presented in this work. Al–Li particle agglomeration, determined to be unconsumed Al–Li, increased with increasing pressure, suggesting that microexplosions were inhibited at higher pressures. Burning rate experiments demonstrated a plateau burning rate effect that occurred in propellant with fine grade (mean diameter: $17\mu \mathrm{m}$) Al–Li particles, whereas the as-received Al–Li-containing (mean diameter: $53\mu \mathrm{m}$) propellant maintained a constant pressure exponent of about 0.39 over all pressures tested. The finer Al–Li propellant had a pressure exponent of 0.59 at pressures below about 4 MPa and a pressure exponent of 0.11 above 4 MPa. Surface imaging of the Al–Li propellant showed a distinctive condensed phase reaction on the surface, which became more prominent with the finer Al–Li particles and at higher pressures: a potential source of the plateau burning rate effect.

基于铝（Al）/锂（Li）的燃料可以潜在地改善复合推进剂的性能并减少盐酸的形成。在Al-Li基复合推进剂中，在0.1 MPa时观察到破裂的微爆炸。但是，Al-Li基推进剂的燃烧特性随压力的变化尚未进行。这项工作介绍了铝锂复合推进剂的燃烧速率的测量以及在各种压力下推进剂表面附近的附聚物生成的量化。被确定为未消耗的Al–Li的Al–Li颗粒团聚随着压力的增加而增加，这表明在较高压力下微爆炸受到抑制。燃烧速率实验表明，在具有优良等级（平均直径：$17\mu \mathrm{米}$）Al–Li颗粒，而按原样含有Al–Li（平均直径： $53\mu \mathrm{米}$）推进剂在所有测试压力下均保持约0.39的恒定压力指数。较细的Al-Li推进剂在低于约4 MPa的压力下的压力指数为0.59，而在高于4 MPa的压力下的压力指数为0.11。Al-Li推进剂的表面成像显示出表面上独特的凝结反应，在更细的Al-Li颗粒和更高的压力下，该反应更为明显：这是高原燃烧速率效应的潜在来源。