Technology Research On The Compact EFP Warhead Of Terminal Sensitive Projectile

A study on the shaping way and structural design of the compact EFP warhead which was loaded in the terminal sensitive projectile has been reported in this paper.First, to analyze the shaping mechanism of the EFP warhead with embedded structure. A deflection will happen at the edge of the embedded structure during the detonation wave propagation because the embedded structure’s sensitive devices can block the detonation wave propagation in the charge of the EFP warhead. Deflected bell-shaped detonation wave acts on a shaped charge liner, resulting in differences among the motions of all micro-units on the liner. According to theories of adiabatic detonation and effective charge along with the semi-empirical formula of detonation wave acting on metal structures, we analyze the motions of all micro-units on the shaped charge liner and qualitatively analyze how the liner might be pressed in.Second, to analyze how shaping mechanism will be affected by embedded components in the EFP warhead of the compact terminal sensitive projectile. There are mainly two factors of embedded components affecting the shaping:(1) Embedded large-diameter components change the shape of the detonation wave to greatly increase the radial pressing speed of the liner in pressing process.(2) The existence of waveguide structure requires an open pore on top of the liner; a portion of detonation products will overflow from the open pore of the liner at a high speed and wash out the metallic material of the open pore after the bell-shaped detonation wave has gathered on the axis of the projectile body and overwhelmed the waveguide. Because the diameter change of the embedded component results in a larger difference in the pressing of the liner, this paper presents an internal-and-external spherical heteroaxial segment liner structure which changes the mass distribution of the liner bus to adapt the changes of embedded components. We adjusted the wall thickness of the waveguide and thickened the material of the open pore to solve the problem of severe eversion caused by detonation products washing out and driving the open pore on the top of the liner arc.Third, to optimize the design of the structural parameters of the internal-and-external spherical heteroaxial segment liner. The structural parameters of the new liner were optimized after selecting the structural parameters of the EFP warhead, including curvatures of both internal and external spheres, radial and axial distances between internal (external) sphere and centre of sphere. An optimization scheme was arranged by introducing a uniform design method and the interactions of structural factors were analyzed by introducing a regression analysis method. A quantitative relation between structural parameters of the liner and EFP indicators was established to find out an optimized structural design. An expectation of an optimization scheme for both speed and appearance of EFP was achieved by simulation. A live ammunition firing test was performed on the optimization scheme equipped with a newly-structured liner, in which showed that its shaping ability was largely in line with the expectation of the simulation-based design and the penetration to the armored target plate was superior to that of the warhead with sphere-conical liner.Finally, to explore the application of new tantalum tungsten alloys on the EFP warhead. Ta-10W alloy features high density and percentage of elongtation, which is applied to the manufacturing of liner and is of great importance to the promotion of the power of the EFP warhead of the terminal sensitive projectile. In this paper, Ta-lOW alloy liner was manufactured by powder metallurgy and loaded with live ammunition and the experimental result was largely in line with the expectation of the simulation-based design, showing that Ta-lOW alloy was feasible for the manufacturing of liner.