Experimental and modeling investigation on the self-propagating combustion behavior of Al-MoO3 reactive multilayer films

In order to probe the self-propagating combustion behavior of aluminum/molybdenum trioxide (Al/MoO3) reactive multilayer films (RMFs), RMFs with varied modulation periods and widths were deposited by the magnetron sputtering method on a glass substrate. Differential scanning calorimetry revealed that thermal reaction was in the solid-solid phase at thin modulation periods (50 nm and 150 nm) and in the liquid-solid phase at the microscale (1500 nm). Furthermore, since X-ray diffraction analysis demonstrated the presence of aluminum oxide, the hot spot and pre-oxidation theory of the interface in Al/MoO3 RMFs allowed logical explanation of the thermal reaction feature. The RMFs achieved stable self-propagating combustion with 50 nm-150 nm modulation periods excited by a laser pulse but not at 300 nm-1500 nm. The average stable combustion velocity was 6 ms(-1) at the 150 nm modulation period and reached 10 ms(-1) for 50 nm. The two-way analysis of variance demonstrated that the effect of the width on combustion velocity was not significant. Thus, we constructed a one-dimensional (1D) combustion velocity model based on heat transfer theory combing experimental data. The model explored the relationship between the stable combustion velocity and the modulation period. Published by AIP Publishing.