The Hugoniot elastic limit (HEL) serves as the critical stress threshold demarcating the transition from purely elastic to elastoplastic response under dynamic loading. Accurate determination of HEL is essential for understanding dynamic mechanical behaviors. Traditionally, HEL is derived from the "double-wave" structure of free-surface velocity profiles. However, wavefront dispersion of the elastic precursor and non-steady-state effects in short-pulse laser-driven experiments introduce systematic deviations in longitudinal sound velocity measurements, limiting precise HEL determination. To address these challenges, a self-consistent interpretation interpretation method integrating macroscopic conservation laws with microscopic thermoelastic simulations is established.
The theoretical framework establishes a self-consistent interpretation equation relating axial stress to longitudinal sound velocity and particle velocity based on momentum conservation. The experimentally measured elastic precursor particle velocity is utilized as the constraint variable. To provide the continuous sound velocity-pressure constitutive relationship, a high-pressure thermoelastic dataset spanning 0–1000 GPa is constructed using density functional theory combined with the mean-field potential method (MFP) and quasi-static approximation (QSA). This approach accounts for ionic vibrational free energy and finite-temperature effects across a broad thermodynamic range. Through iterative solution of the self-consistent interpretation equation which physically corresponds to the dynamic catch-up process where high-stress perturbations propagate faster than low-pressure wavefronts—the HEL and in-situ longitudinal sound velocity are determined simultaneously without relying on ambiguous wavefront arrival time measurements.
The validity of this approach is verified using diamond as a benchmark material. The predicted elastic moduli agree with static compression data within 0.4% relative deviation up to 15 GPa. For gas-gun experiments with peak stresses reaching 1 TPa, the reinterpreted HEL values show less than 2% relative deviation from standard experimental benchmarks, quantitatively characterizing the crystalline anisotropy, where the longitudinal sound velocity follows the sequence 111 > 110 > 100. For laser-driven experiments where non-steady-state attenuation previously caused systematic underestimation, the HEL values are corrected upward by 8%–13%, reconciling discrepancies between different loading platforms.
This hybrid approach enables retrospective correction of non-ideal experimental effects through solely through data reanalysis, providing high-precision dynamic constitutive parameters under extreme conditions without requiring specialized experimental configurations. The datasets presented in this paper are openly available at https://www.scidb.cn/s/zyMJve.