Combustion and red emission behavior of Sr(NO3)2/aluminum–magnesium alloy-based pyrotechnic compositions: effects of formulation and preparation method

Abstract

This study investigates the effects of formulation and processing on Sr(NO3)2/Aluminum-Magnesium (Al-Mg) alloy with NH4Cl/NC/PVC subsystem pyrotechnic compositions. Three methods of preparation were compared: tetrahydrofuran-based homogenization, acetone-based separate mixing, and acetone-based one-pot mixing. The acetone-based method featuring separate Sr(NO3)2 incorporation significantly enhanced both the burning behavior and flame color quality. Discrepancies between experimental and equilibrium temperatures highlight incomplete condensed-phase and secondary gas-phase transformations. Chromaticity analysis indicated dominant wavelengths of 603.5–631 nm and color purities of 69.9–81.7% for the investigated compositions. The spectral analysis showed a high red spectral contribution for all samples. The NH4Cl/NC/PVC ratio complexly influences burning rate. These results elucidate the relationships among formulation, preparation method, combustion characteristics, and red-light emission performance of Sr(NO3)2/Aluminum-Magnesium-based pyrotechnic compositions. The observations provide a basis for further refining preparation procedures and formulation strategies to achieve stable combustion characteristics and consistent red-light emission, which are important for applications requiring precise control of combustion behavior and optical performance.