Cold extrusion of a shaped charge liner preform with hyperboloid structure: simulation and experiment

In this work, a novel five-step cold extrusion forging technology was proposed for fabricating a shaped charge liner with hyperboloid structure feature, in which three steps forming to develop the macroscopic hyperboloid shape and two steps annealing treatments to improve the microstructure and property of the liner. Besides, the preforming process was the focus of this investigation because the size structure, microstructure, and texture of the preform play a crucial role in the manufacture of the final forming process due to the heredity of dimension and microstructure, which also provides powerful process reference with the following forming steps. Based on the ABAQUS finite element (FE) platform, the cold extrusion process of the shaped charge liner preform was simulated, and the influences of forming parameters such as the initial billet size and friction coefficient between billet and dies on forming load, cavity filling, and strain distribution of the preform were investigated, respectively. The simulation results show that the optimal parameters of initial billet diameter and friction coefficient between dies and billet in cold extrusion preforming of shaped charge liner are 50 mm and 0.1, respectively. Additionally, the strain distribution of the shaped charge liner in the cold forming process was analyzed in detail. Finally, the experiment of the cold extrusion of the shaped charge liner preform was carried out to verify the feasibility of the cold extrusion process and the correctness of the simulation results.