Research Of The Warm Forming In V-shape Free Bending Of5A06Aluminum Alloy Tailor Welded Blanks

Aluminum alloy has the advantages of light weight, corrosion resistance,environmental friendly and many other features that make it to be an excellent material forautomobile body manufacturing. Tailor welded blanks technology is combined SeparationStamping Forming with Integral Forming. Comparing with the traditional steel body, it tend tobe with a lower energy consumption, better appearance and more safety through usingaluminum alloy plate on auto body manufacturing. However, the plasticity of aluminumalloy sheet is poor at room temperature, and also it is easy to have weld moves in formingprocess, so that is difficult to control in the forming process. Therefore, this research is todo heating test on the aluminum alloy tailor welded blank, which can give play to theadvantage s of both aluminum alloy plate and tailor welded board technology that has highpractical significance and economic value.This paper focused on forming features of5A06aluminum alloy plate. At first, it tookdifferent thickness5A06aluminum alloy plate and made the FEM model of V-shaped warmfree bending. Then, it observed the V-shaped warm free bending forming process atdifferent forming temperature，friction factor，radius of the round corner of concave-convexdie and registration clearance. After that, it discussed the effects on the weld misalignmentand springback by such factors. In the end, we analyze the influence of these factors onformability of the part by orthogonal experiment, regarding the weld line movementnumerical and Springback angle as a forming quality evaluation index.A bending die was designed and manufactured based on FEM stimulation result.Thermal bending experiment for5A06aluminum alloy plate in annealed condition wasconducted. V-shaped warm free bending experiments for tailor-welded blanks with vacuumelectron beam welded straight and45degree weld line were also conducted respectively.Constant thickness cushion block structure was designed，so the radius of the round cornerof concave-convex die could be changed in one die，and the experiment cost was saved. Effects on the weld misalignment and springback by parameters such as formingtemperature, radius of the round corner of concave-convex die，friction factor，registrationclearance were analyzed on the basis of the experiments. Comparing the experiment resultsto the FEM stimulation result，it showed that weld line had a relatively large migration andalso the springback were obvious after the different thickness aluminum tailor-weldedplates were V-shaped warm free bent. Such phenomenon could be avoided if reasonableparameters were taken. The weld offset and springback can be reduced by using theReasonable parameters as175℃,30#engineoillubricants, mold gap1.2mm, fillet radius ofthe punch is10mm, the radius of die is12mm.The aluminum alloy tailor welded blankswas minimized the weld off set minimum (3.5mm) and the rebound angle (2.4).In a word,using reasonable mould structure and appropriate process parameters could obtainwell-formed aluminum tailor-welded parts.