Study On Automobile A-alloy Wheel Stagger Spinning Forming Process

Compared with conventional power spinning, stagger spinning has unique advantages. Recently, stagger spinning technology has been widely used in the fields of aerospace, aviation and military industry, etc. However, the factors affecting the tube stagger spinning process are too numerous and too complex; it is time resuming and uneconomical to determine the technical project by experimentation. In order to systematically study the Stagger Spinning of car wheels, the mechanics model is found On the basis of the wheels Stagger Spinning Process analysis. And the mechanical properties and performance of the organization of the wheel is analyzed combine with numerical simulation results.Using finite element analysis software SIMUFACT on Stagger Spinning wheels simulate the process, obtained the stress and strain distribution during Spinning, analyzed the flow law of metal and plastic forming mechanism of the deformation zone. The metal in compressed zone flows along the radial, axial and tangential direction, mainly the axial direction. The contact field between the spinning rollers and the billet is in the three-dimensional stress condition, where as the other field is mainly in the two dimensional compressive and one dimensional tensile stress conditions。 Axial strain is mainly a compressive one, whereas tangent or radial strain is mainly a tensile one.Simulation different axial stagger value and radial reduction on effects of the equivalent stress and the spinning force. Obtained the variation of spin pressure and effective stress of deformation zone. Spinning force increasing with the stagger value first and then decreases, when the stagger value is 2mm, spinning force is minimum, and the equivalent stress of the deformation zone distributions evenly the most, in favor of the blank evenly deformation. When Radial reduction is 2mm,1.5mm,1.5mm, the mean square of radial spinning force is the minimum, at this point blank uniform deformation. Effective stress of deformation zones are also under this group reduction effect is most uniform.Aluminum car wheel hub microstructure and mechanical properties is analyzed with numerical simulation, before and after deformation by Stagger Spinning. Metallographic analysis showed that spinning wheel grain refinement, the formation of fibrous tissue, so that more uniform, bridging the cast structure defects and improve the density of the hub, to improve organizational performance hub. Analysis of the tensile properties, obtained wheel spinning process to improve the strength, hardness, ductility decrease hub, an overall improvement of the mechanical properties of the hub; SEM fracture analysis, the spinning process which changes the dimple fracture of casting specimen to mixed-rupture fracture of quasi-cleavage and dimples reduces material’s plastic, which is consistent with the results of the tensile experiment.