Research On Multi-mode-one-off Ironing Process Fot Cartridge Case

The multi-mode ironing process can fully use the plastic deformation ability ofmaterial and reduce process. It has been widely used in the manufacture of thin-walledlong cylindric part with bottom-thickness. With the rapid development of manufacturingtechnology and the upgrade of product competition, the urgent need is the analysis ofdeformation mechanism to guide the actual production, so that high efficiency of thereliable mass production can be achieved.In this dissertation, a mechanics analysis is conducted for multi-mode ironing processand the export stress equation of die is given. It has been found that the ironing proceduresare affected in big style by the factors like matrix cone angle, thinning coefficient, heattreatment and friction factors.As the research object, cartridge case is a very typical ironing part with highprecision. The current process of a certain type cartridge case contains three times citedlong, with annealing and pickling as the auxiliary procedure, too various process to limitthe production efficiency. Using the finite element software Deform to simulate the wholeironing process of cartridge case, metal forming effect, stress, forming force and thicknessdistribution were obtained. The one-off continuous ironing process was inaugurated onthis basis, focused on the influence of thinning coefficient and matrix cone angle, and akind of better multi-mode ironing distribution and reasonable combination of matrix coneangle was put forward. The blank shape and mold structure were also optimized to finallydetermine the one-off continuous ironing process.The experimental mould of cartridge case ironing was designed and manufacturedbased on the one-off continuous ironing process. The practical blank was formed indifferent working conditions and different lubrication conditions and the work piece metthe demand of surface quality and basic size requirement of cartridge case, so thefeasibility of the one-off continuous ironing process to complete cartridge case extensionwas verified. Some defects appeared on the work piece such as tensile failure, transversefissure, port longitudinal crack and body line marks were analyzed, and forming quality was improved significantly after the corresponding improvement of the blank size, theprocess can provide evidence for manufacturing cartridge case efficiently and in a largescale in the future.