• • HEC-W (Hf, Ta, Zr, W)C achieves oxidation resistance at 3600°C, surpassing the previous 3000°C limit for UHTCs, with a linear ablation rate of 2.7 μm s−1 under a heat flux of ~30 MW m−2, enabling hypersonic applications exceeding Mach 25.
• • The protective oxide layer consists of high-melting-point W particles (3422°C) embedded in a molten (Hf,Me)6(Ta,Me)2O17 matrix (melting point ~2450°C), which seals defects and enhances viscosity, reducing oxygen diffusion and material degradation.
• • Oxidation kinetics follow a parabolic trend with a high activation energy of 149.7 kJ mol−1, indicating diffusion-controlled, highly protective behavior, critical for long-duration thermal exposure.
• • The laser oxidation platform can generate and sustain temperatures up to 3809°C within seconds, enabling rapid screening of HEC compositions and accelerating the discovery of extreme-temperature materials.