The construction of structural defects in MoAlB thin films by leveraging the enhanced Kirkendall effect for improved infrared stealth performance

Abstract

MoAlB, known for its exceptional oxidation resistance and anti-ablation properties, holds significant promise as a protective thin film for high-temperature components in military equipment. However, the high thermal conductivity of MoAlB poses a challenge to its compatibility with infrared stealth performance. In this study, structural defects were intentionally implanted into the MoAlB thin film by leveraging the amplified Kirkendall effect to hinder heat propagation. The results revealed that the MoAlB MAB phase thin film with a notable amount of edge dislocations was achieved by subjecting the post-annealed (Mo–B)/Al nanostructured multilayers (NMs) to an elevated temperature of 700 °C. The room-temperature resistivity of the thin film was 1.43 μΩ m. Furthermore, the infrared emissivity of the thin film was assessed within the mid-infrared wavelength range, ranging from 0.11 to 0.25. Simultaneously, the resulting thin film was found to possess a low thermal conductivity of 11.44 W m−1 K−1, consequently achieving excellent infrared stealth capability.