Advancements in removal mechanism and precision manufacturing of (TiZrHfNbTa)C high-entropy ceramics with nanosecond laser

(TiZrHfNbTa)C high-entropy ceramic is a category of ultra-refractory materials essential for applications in extreme environments, such as nuclear fusion reactors and aerospace thermal protection systems. Nanosecond lasers provide a new approach for achieving excellent surface integrity and dimensional accuracy. The influence of nanosecond lasers on the material removal mechanism and surface characteristics was systematically investigated through a combination of computational modeling and experimental validation. Equimolar HfC, TaC, ZrC, TiC, and NbC powders were employed as precursors to prepare (TiZrHfNbTa)C high-entropy carbide bulk ceramics by means of 1 spark plasma sintering, and as shown here, the resultant ceramics were synthesized through this specific sintering technique. The samples were machined with a nanosecond laser at power levels of 4, 7, 10, and 13 W. The results show that nanosecond laser ablation induces a hierarchical oxidation sequence: Zr and Hf undergo preferential oxidation due to their lower ionization energies, followed by Ti, and finally Nb and Ta. A laser power of 10 W was found to provide a critical balance between manufacturing capability (kerf width = 161 μm and heat-affected region