Combustion properties and mechanism of Al-Mg-Li/RDX composites

To improve the ignition and combustion performance of aluminum, this study prepared Al-Mg-Li ternary alloys using the centrifugal atomization method, and based on this, prepared-Mg-Li/RDX composites with different mass ratios. The combustion behavior of the Al-Mg-Li/RDX composites was systematically studied, monitoring their combustion state, combustion, pressure, and pressure rise rate. Results demonstrated that lithium incorporation effectively disrupts the dense oxide layer on aluminum particles, significantly enhancing combustion reactivity. The addition of RDX accelerated more vigorous oxidation reactions in the Al-Mg-Li alloy, leading to more complete combustion of the powder. As RDX content increased, combustion duration shortened progressively while peak pressure and pressure rise rates continued to rise. Especially under the condition of 30% RDX content, the heat of combustion, peak pressure, and pressure rise rate of the Al-Mg-Li/RDX sample all superior to those of the Al/RDX and Al-Mg/RDX samples with the same ratio, exhibiting more concentrated exothermic characteristics and a shorter combustion duration. Furthermore, comprehensive characterization using SEM, EDS, XRD, and XPS techniques was conducted to elucidate the combustion mechanism of the Al-Mg-Li/RDX system. This research provides both theoretical foundations and experimental evidence for developing next-generation high-performance aluminum-based alloy fuels.