Study on a novel Al-B-Li alloy powder with high enthalpy of combustion

Abstract

ABSTRACT To develop aluminum-based alloy fuels with high energy release levels and good storage stability, the series of Al-B-Li alloy powders were prepared using high-temperature gas atomization. Al-4B-5Li meets the batch preparation requirements, with the mass combustion enthalpy of 31,101 J/g, exceeding the theoretical value of pure Al powder. XRD, SEM/EDS, XPS, TG-DTA, and other methods were used to characterize the alloy powder. The results showed that at 680℃~800°C, “channels” favorable for oxygen diffusion are formed inside the particles, which promotes the complete oxidation of Al-4B-5Li at 1300°C. Al-4B-5Li exhibits a total heat release of 6317 mJ/mg and an oxidation weight gain ratio of up to 95.0%, compared to just 8.39% for pure Al powder. In addition, Al-4B-5Li has good storage stability and lower energy attenuation compared to Al-5Li. After being placed in air for two weeks, the mass combustion enthalpy still exceeds 29,500 J/g, with a decay rate of only 4.52%. And the attenuation rate of Al-5Li is 10.17%. Al-4B-5Li has excellent combustion heat, thermal oxidation performance, and storage stability, and has good application prospects in the field of energetic materials.