To further investigate the factors influencing EFP formation quality, this study focused on the structure and materials of the liner as well as the charge height. Using LS-DYNA software, a 160 mm diameter EFP simulation model was established to systematically study the influence of liner structural parameters, charge structure, and liner material properties on EFP formation quality. The results show that when the curvature radius of the liner decreases from 160 mm to 80 mm, the head velocity of the EFP increases by 10.2% (from 2 495 m·s-1 to 2 749 m·s-1). When the liner wall thickness decreases from 10 mm to 1 mm, the head velocity increases by 627.8% compared with the original value (from 711.9 m·s-1 to 5 181 m·s-1); however, when the liner wall thickness is reduced below 4 mm, the EFP fractures during formation, which compromises its structural integrity. Additionally, a variable wall thickness design for the liner is proposed. For an EFP with a tapered thickness structure (4 mm at the top gradually thinning to 2 mm at the edge), the velocity can be increased by 8.1% while maintaining integrity (increasing from 2 749 m·s-1 to 2 973 m·s-1). Furthermore, multiple liner materials are discussed, with an analysis of their penetration performance. In the study of charge height, a critical threshold value (150 mm for charge height) is determined, beyond which the velocity improvement efficiency decreases significantly. The final optimized solution is proposed: using a liner with a curvature radius of 80 mm, a variable wall thickness structure (4 mm thick at the center tapering to 2 mm at the edge), made of tungsten-copper alloy or copper, and a charge height of 150 mm. This configuration enables the EFP to maintain structural integrity and aerodynamic shape while achieving head velocities ranging from 2 794 m·s-1 to 3 522 m·s-1. These results provide a new parameter-matching strategy and theoretical basis for the design of EFP warheads.
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