Synthesis of hafnium carbide (HfC) via one‐step selective laser reaction pyrolysis from liquid polymer precursor

Abstract This study introduces a novel one‐step selective laser reaction pyrolysis (SLRP) method for synthesizing hafnium carbide (HfC), an ultrahigh‐temperature ceramic (UHTC). Unlike conventional methods that involve multiple steps, including crosslinking and pyrolysis, this approach combines both processes into a single laser‐driven step, reducing time and energy consumption. The CO 2 infrared (IR) laser ( λ = 10.6 µm) used in this technique enables localized heating up to 2000°C within seconds, facilitating the conversion of a liquid polymer precursor into HfC. Material characterization using x‐ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) confirmed the crystallinity and phase purity of the synthesized HfC powder. To study energy absorption, thermal and photo‐activators were added to the precursor before laser exposure. The thermal activator had a negligible impact on reflectivity but yielded a pure HfC phase, demonstrating the potential for optimized precursor formulations to enhance efficiency without compromising purity. The one‐step process was successfully applied for additive manufacturing, depositing HfC coatings onto carbon–carbon (C/C) composite substrates. This technique eliminates the need for high‐temperature furnaces, enabling rapid fabrication of UHTC components and advancing scalable, energy‐efficient manufacturing. The study highlights its potential for energy, aerospace, and other extreme environment applications.