Abstract: In order to explore the steady-state combustion of high-metal Al-Mg alloy hydro-reactive metalfuels for water ramjet engines，experiments were conducted to study the primary combustion and the secondarycombustion of propellant with the Al-Mg alloy content 80%.Oxygen bomb calorimeter was used to collect the sol.id products of primary combustion.The secondary combustion was simulated in the high temperature tube furnaceby using the solid products of primary combustion and water vapor.Thermal performance of Al，Mg and Al-Mg al. loy was analyzed by thermogravimetric analysis(TGA).The solid products were characterized by using scanning electron microscopy(SEM)x-ray diffraction(XRD)，chemical analysis method.TGA traces in air indicate that theoxidationonsettemperature，(530℃)of Al-Mg alloy powders is lower than that(600℃)of Mg and the oxida.tion performance of Al-Mg alloy powders is better than that of Al in case II.There were MgO，MgAl，Mg2Al3， MgAl2 produced by Mg17Al12 in the primary combustion. There were MgO，Al and Al2MgO4 in the products of sec.ondary combustion.The content of residual aluminum increases with the increasing of temperature of the tube fur. nace，and then decreases.It is thought that the combustion of magnesium in Al-Mg alloy occurs first and the com.bustion of aluminum happens later.

Key words: Al-Mg alloy；Hydro-reactive metal fuel；Solid products；Primary combustion；Secondary com. bustion

摘要： 为了探索在水冲压发动机中高金属含量铝 /镁合金水反应金属燃料的稳态燃烧，开展了其一次燃烧和二次燃烧实验研究，其中铝 /镁合金含量达到 80%。采用氧弹量热仪收集一次燃烧固相产物，并将一次燃烧固相产物置于水蒸气高温管式炉中模拟二次燃烧。采用 TGA对铝、镁和铝 /镁合金进行了热性能分析，并采用 XRD，SEM及化学分析方法对铝 /镁合金和推进剂的一、二次燃烧固相产物进行了表征。结果表明，铝/镁合金的启动氧化温度 530℃优于镁的 600℃，铝/镁合金在第二阶段的氧化性能优于铝的。铝/镁合金为 Mg17Al12，一次燃烧固相产物中主要存在 MgAl，Mg2Al3，MgAl2等合金相和 MgO，在二次燃烧的固相产物中有 MgO，Al和 Al2MgO4，其中剩余 Al的含量随着管式炉温度增大先增大后减小。分析认为铝 /镁合金在燃烧过程中镁先行发生了反应，而后其中的铝才发生反应。

关键词: 铝/镁合金；水反应金属燃料；固相产物；一次燃烧；二次燃烧