Impact-induced energy release of typical HCP metal/PTFE/W reactive materials: Experimental study and predictive modeling via machine learning

Zirconium, titanium, and other hexagonally close-packed (HCP) metals and their alloys are representative high specific strength, high reaction enthalpy, and high thermal conductivity structural materials. In this study, two typical HCP metals, zirconium, and titanium, were applied to reactive materials (RMs) to prepare Zr/PTFE/W RMs and Ti/PTFE/W RMs, validating the feasibility of HCP metal/PTFE/W RMs. The impact response process of typical HCP metal/PTFE/W RMs under high-velocity dynamic loads was studied using shock equations of state (EOS) based on porous mixtures and chemical reaction kinetics equations. An improved hemispherical quasi-sealed test chamber was employed to measure the energy release characteristic curves of 10 types of Zr/PTFE/W RMs and Ti/PTFE/W RMs under impact velocities ranging from 500 m/s to 1300 m/s. The datasets of the impact-induced energy release characteristics of HCP metal/PTFE/W RMs were established. Additionally, the energy release efficiency of HCP metal/PTFE/W RMs under impact was predicted using the support vector regression (SVR) kernel function model. The datasets of Zr/PTFE/W RMs and Ti/PTFE/W RMs with W contents of 0%, 25%, 50%, and 75% were used as test sets, respectively. The model predictions showed a high degree of agreement with the experimental data, with mean absolute errors (MAE) of 4.8, 6.5, 4.6, and 4.1, respectively.