<p>Energy structural materials (ESM) have emerged as a critical frontier in the research of novel warhead constituents, primarily attributed to their superior mechanical performance and impact-induced energy release characteristics. This study systematically investigates the damage effects and energy release mechanisms of non-equimolar ratio Zr₄₂Ti₁₅Nb₂₀Ta₂₀Al₃ refractory high-entropy alloy (RHEA) fragments against spaced targets under high-velocity impact loading. Initial material characterization through quasi-static and dynamic compression tests confirms that this RHEA-ESM possesses the distinct advantages of high strength and high toughness. Specifically, the quasi-static yield strength of 1111.3 MPa surges to 1976 MPa at a dynamic strain rate of 4900 s⁻¹. Furthermore, ballistic impact tests reveal that as the impact velocity is elevated from 832 to 1401 m/s, the fragmentation degree intensifies significantly. Correspondingly, the energy release efficiency jumps from 11.8% to 34.8%, with the specific energy release reaching a maximum of 4.67 kJ/g. Regarding the target damage mechanisms, analysis of the spaced targets demonstrates a shift in the RHEA-ESM damage mode, evolving from single kinetic energy (KE) plugging to a coupled KE-chemical energy effect. This transition is evidenced by the continuous expansion of the after-effect target damage area with increasing velocity. Finally, fuel tank ignition tests strongly validate the fragment’s capability to effectively penetrate fuel tanks and ignite diesel, exhibiting a combustion duration of up to 251 ms, thereby fully demonstrating its highly efficient energy-coupled damage capability.</p>