The Numerical Simulation And Experimental Study Of Automobile Axle Housing Bulging Process

In recent years the automotive industry has become a pillar industry of thenational economy with its rapid development and the industry of auto parts isalso developing rapidly as the basis of the automotive industry. At the same time,there exist some aspects which have restricted the development of theautomotive industry such as environmental pollution, energy shortages and rawmaterial costs, which makes the lightweight of automotive structuresparticularly important. Automobile axle housing is a key automotive drivelinecomponent which can support reducer and differential and transfer torque. As aresult, it requires higher strength and stiffness which can realize the lightweightof automotive structures and ensure the axle housing to meet the servicerequirements of the premise, which is of great significance.Under the background of automobile structure lightening， the traditionalprocess exist so many defects. In this paper the theoretical analysis, numericalsimulation and experimental analysis are used to study the mechanical bulgingprocess of automotive axle housing. The process includes both ends of the axletube diameter screw compressor packages and central lute package bulgingprocess. The numerical simulation of the spinning and necking process of squaretube diameter is studied based on the ABAQUS software platform. It can predictthe metal flowing laws in the forming process, stress and strain distribution, theaxial length and the wall thickness variation and the possible defects. Theresults show that the four corners contact the die firstly with the plasticdeformation and the maximum stress and strain and the maximum wall thickness.The four corners have the biggest possibility to have buckling and foldingdefects in the necking process so it should be controlled in the actual production.With the increasement of the necking process the cumulative amount ofdeformation, the equivalent strain and the wall thickness increases, which canhelp improve the service life of the axle housing.The stress state of the deformation region is analyzed in deeply and we usethe FEM software MARC to simulate the bulging process. The potential areaswhich is easy to produce tension fracture and collapse are forecasted andobtained metal flow， stress and strain distribution and wall thicknessdistribution. Analyze the effect on wall thickness distribution of technologicalhole shape and length， and proposed a forming process which use a triangulargroove in the central of the lute. Design a mold to do physical experiment to verify the correctness of numerical simulation， and research the reboundphenomenon and compensation produced in the process. The results show thatthe experimental result is closer to numerical simulation and the center parts ofaxle housing undertake greater tangential compressive stress and strain whicheasily cause the wrinkling defects. Transition regions bear greater tangentialtensile stress and tensile strain which cause wall thickness reduction and severecases can produce tension crack phenomenon. It is seriously affect intensity andlength of service of the axle housing. Increasing triangular groove caneffectively alleviate the wrinkle defects in central areas and provide a valuablereference for the subsequent mass production.