Research On Isothermal Precision Forming Process Of 7A04 Aluminum Alloy Complex Connector Parts

This paper investigated isothermal precision forming technology of 7A04 aluminum alloy connector parts, using the finite element simulation and experimental study.7A04 aluminum alloy, which is one of Al-Zn-Mg-Cu alloys, is a typical ultra-high strength aluminum alloy with high specific strength and hardness, good workability, corrosion resistance and toughness. The alloy has been widely used in aviation and aerospace fields. The precision isothermal forming process of 7A04 aluminum alloy connector parts was simulated by commercial FEM software DEFORMD-3D and also studied experimentally.Material properties of 7A04 aluminum alloy were analyzed through hot simple compression using Gleeble testing machine. High temperature deformation behavior characterized by flow stress at different strain rates and microstructure evolutions were investigated.According to structural characteristics of the component, the isothermal forming process was desiged and optimized using DEFORM-3D software. Temperature change, equivalent stress and strain distributions were obtained. The influences of various parameters on forming process were also analyzed.Tooling and die were desiged, and process experiment were carried out.The results show that dimensional tolerance could be controlled in the range±0.2mm, and surface roughness Ra is not more than 3.2μm at the forming speed of 0.5-1.0mm/s. Forming temperature has a great effect on surface quality and deformation resistance. Good surface quality could be obtained at relative low temperature. Mechanical property testing shows that isothermal precision formed parts possesses excellent mechanical properties and the fiber flow line is almost aligned with the geometrical shape of the parts.