Al–Mg–Li ternary alloy particles can be a promising metal additive to replace aluminum in solid propellants to improve combustion efficiency by reducing agglomeration during combustion. In this paper, Al–Mg–Li ternary alloy was prepared and its basic physical and chemical characterization parameters were obtained by SEM-EDS, ICP-AES, and XRD analysis. The ignition and combustion characteristics of single Al–Mg–Li particles under different pressures were investigated by using a self-developed experimental setup. The ignition process and combustion flame structure of Al–Mg–Li particles were significantly affected by the increasing pressure, and the ignition delay and combustion time decreased. The ignition mode was clearly identified: surface ignition (0.1–0.2 MPa) and gas phase ignition (0.4–1.2 MPa). Al–Mg–Li particles showed white-pink flame during combustion, and the characteristic peaks of AlO, MgO, and Li were identified, confirming that the particles performed a gas-phase combustion at pressures above 0.4 MPa. The combustion temperature of Al–Mg–Li particles could exceed 3000 °C when the pressure surpassed 0.6 MPa. The composition of different regions in the condensed combustion products were analyzed. Reaction mechanism was proposed to reveal the addition of elemental Mg and Li could improve the ignition and combustion characteristics of Al, especially at higher ambient pressures.

中文翻译：

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Al-Mg-Li合金颗粒在高​​压下的着火和燃烧

Al-Mg-Li三元合金颗粒可以成为一种很有前途的金属添加剂，可以替代固体推进剂中的铝，通过减少燃烧过程中的团聚来提高燃烧效率。本文制备了Al-Mg-Li三元合金，并通过SEM-EDS、ICP-AES和XRD分析获得了其基本物理和化学表征参数。采用自行开发的实验装置研究了不同压力下单个Al-Mg-Li颗粒的着火和燃烧特性。 Al-Mg-Li颗粒的着火过程和燃烧火焰结构受压力增加的影响显着，着火延迟和燃烧时间缩短。点火模式明确：表面点火（0.1-0.2 MPa）和气相点火（0.4-1.2 MPa）。 Al-Mg-Li颗粒在燃烧过程中呈现白粉色火焰，并识别出Al2O、MgO和Li的特征峰，证实颗粒在0.4 MPa以上的压力下进行气相燃烧。当压力超过0.6 MPa时，Al-Mg-Li颗粒的燃烧温度可超过3000℃。分析了冷凝燃烧产物中不同区域的组成。提出的反应机理揭示了元素镁和锂的添加可以改善铝的点火和燃烧特性，特别是在较高的环境压力下。