Experimental Research On Materials And Forming Of Electroformed Shaped Charge Liner

Shaped charge liner is an indispensable component of High Explosive Anti-Tank?HEAT?,which has urgent demand for new materials.Copper is a common kind of material used into the liner,but its performance still needs to be improved;amorphous alloy has been applied into the liner overseas due to its excellent performance,so it makes sense to study high-performance copper and amorphous alloy.In addition,compared with other conventional manufacturing methods of shaped charge liner,the liner manufactured by electroforming has its own unique advantages,for example,the liner has high purity of material,dense tissue and high material availability.Hence,the research on materials and forming of electroformed shaped charge liner has been launched.Firstly,the electroforming of copper in the solution with high H₂SO₄ and low CuSO₄·5H₂O concentration has been carried out.In order to study the tensile strength and elongation ratio of copper deposits,the cylindrical electroforming copper experiments have been conducted in three CuSO₄·5H₂O concentrations.The results show that the tensile strength of copper deposits obtained under 20g/L,40g/L and 60 g/L were respectively 526 MPa,435 MPa and 402 MPa,while the elongation ratio were30%,24%and 28%.Secondly,the electroforming of amorphous Ni-P alloy in an electroforming bath containing Ni?NH₂SO₃?₂ and H₃PO₃ has been developed.The pulse current and friction-assisted technology with ceramic microbeads were used to find the influence on phosphorus content,crystallographic texture,macro morphology and micro hardness of changing three pulse parameters,current density and rotated speed of cathodic mandrel.The results show that the phosphorus content changed with the variation of three pulse parameters,and friction-assisted technology with ceramic microbeads could obviously improve the surface quality of deposits while the phosphorus content decreased.In addition,the degree of amorphization of deposits increased with the increasement of phosphorus content while the micro hardness had the opposite changing trend.Thirdly,as for single conical liner,an optimal design method of electric field in COMSOL has been adopted to optimize its electric field of electroforming.Primarily,the suitable initial distance between cathode and anode was confirmed.Then the optimal design was conducted by changing anode profile and adding shield.Eventually,the ratio of the maximum to the minimum of current density on top end-face and conical surface of cathodic mandrel reduced from 1.799 to 1.498 while the ratio of the maximum to the minimum of current density on conical surface end dropped from 1.455 to 1.133.Finally,based on above research results,the electroforming of copper shaped charge liner has been carried out.And the forming quality,microhardness,axial thickness distribution and metallographic structure of the electroformed liner were analyzed.The results show the liner surface was smooth and had high surface quality with no visible defects.The microhardness of top end-face was 116.03 HV,and the microhardness of conical surface was 108.9 HV.Besides,the axial thickness and grains distribution of the liner deposits were quite uniform.