Study On The Warm Extrution Forming Process Of Aluminum Alloy Electrical Connectors Shell

Traditional methods of forming shell parts generally fall into 3 categories: machining, die-casting and cold extrusion. However, each of them has its own deficiencies. As for machining, it can cut off metal fibrous tissue and thus leads to poor performance of materials'mechanical properties and low productivity. Die-casting is likely to produce trapped holes inside the metal and cracks on surface of the metal. Cold extrusion tends to strengthen deformation resistance of the metal which will result in short service life of the die.As the research object of this paper, 6A02 aluminum alloy electrical connector shell part, a tube part with a through-hole in the middle and double-sided holes, is featured by its complex shape, thin wall thickness and high-demand for dimension precision. Therefore, this paper proposes that warm extrusion, a favorable technology in recent years, should be adopted in forming 6A02 aluminum electrical connector shell part in order to avoid deficiencies brought by traditional methods, promote productivity, save raw materials and reduce production cost.First of all, the paper establishes a three-dimensional model of the shell part and then analyzes its structures, including analyses of extrusion process, calculation of blank size, calculation of deformation degree, calculation of warm extrusion pressure and selections of extrusion equipment etc. Based on the analyses above, the paper builds a two-extrusion-forming process plan with pre-forming and final-forming included.Then guided by the proposed process plan, the paper designs the extrusion die, conducts numerical simulation of warm extrusion process with DERORM-3D finite element software, and analyzes the flow pattern of 6A02 aluminum alloy extruded metal as well as the effects of different temperatures, extrusion speed, friction factor and other parameters on the extrusion process, which help to set reasonable warm extrusion process parameters.Finally, the process experiment is carried out after the optimization of warm extrusion process parameters by using DERORM-3D finite element software, and then suggestions are proposed to resolve problems arising in the experiment. Meanwhile, it concludes that compared with other lubricants, phosphating agent can help achieve the best effect.