包覆式活性 EFP 成型机理与规律研究

The formation mechanism of coated reactive explosively formed projectiles (EFP) and the influence laws of liner structure on the formation behavior of EFP are studied. A Lagrange-Euler numerical simulation model of coated EFP is established, which reveals that the formation process of coated reactive EFP mainly includes axial double-liner impacting phase, radial coat closing phase and metal precursor penetrator stretching phase. In the axial double-liner impacting phase, the velocities of two liners rise in turns with axial kinetic energy transfer. In the radial coat closing phase, the copper liner folds forward to the axis and its tail completely coats the reactive liner. It is mentioned that a metal precursor penetrator is formed on the edge of copper liner. After that, the metal precursor penetrator is stretched and even fractured over time. Further, the influences of the shape parameters of copper and reactive liners on the coating formation are studied. With the decrease in the copper liner edge thickness from 2. 0 mm to 0. 5 mm, the closing time decreases from 57. 9 μs to 23. 9 μs, meanwhile the tip velocity increases from 1 851 m / s to 2 370 m / s, and the penetrator length increase from 76 mm to 110. 5 mm. As the curvature radius of copper liner decreases from 60 mm to 40 mm, the closing time of coating decreases from 42. 1 μs to 28. 1 μs, meanwhile the tip velocity increases from 1 789 m / s to 2 242 m / s, and the penetrator length increases from 66 mm to 100 mm. With the decrease in the reactive liner thickness from 6mm to 2mm, the closing time decreases from 52. 0 μs to 32. 1 μs, meanwhile the reactive liner mass decreases from 6. 47 g to 2. 37 g. With the decrease in the reactive liner diameter from 32 mm to 16mm, the closing time decreases from 34. 4 μs to 30. 8 μs, meanwhile the reactive liner mass decreases from 6. 42 g to 1. 61 g. The results can provide guidance and reference for the design of coated reactive EFP shaped charge.