Infrared-emitting pyrotechnic compositions based on Al/Mg/PTFE with PAC/HD-70 binder: Characterization and performance evaluation

Background/Aim: Infrared-emitting pyrotechnic components are key components of decoy systems used to defeat infrared-guided threats by reproducing target-like thermal signatures. This study developed and characterized an Al/Mg/PTFE infrared-emitting composition using a PAC/HD-70 binder to improve both infrared performance and mechanical strength. Methods: Compositions with varied Al/Mg ratios, particle sizes, binder systems, and compression densities were prepared and characterized for combustion behavior, infrared emission, burning rate, and compressive strength. Results: Increasing Al content enhances infrared intensity and shifts the peak wavelength to shorter ranges, whereas increasing Mg speeds up the burning rate. Most notably, the PAC/HD-70 binder provided a compressive strength of 16.78 N.mm-2 due to covalent crosslinking, which is significantly higher than that of traditional thermoplastic binders. Additionally, using ultrafine PTFE (3.6 µm) was found to cause incomplete combustion. Conclusion: The study establishes that the infrared emission and combustion behavior of these compositions can be effectively controlled by adjusting the Mg/Al ratio and particle sizes. The implementation of the PAC/HD-70 binder system is a critical breakthrough, providing the necessary mechanical toughness to withstand ignition pressures (approx. 70 atm) while maintaining high spectral performance for next-generation infrared decoys.