Study In Large Deformation And Invalaid Behaviors Of 2A12 Al Uminium Alloy Butted Joints

With the development of vehicle industry and to meet the requirements of lightweight vehicles, the new generation of high-strength aluminum alloy is widely used in the frame of cars, the corresponding aluminum alloy welded joints were also introduced to a large number of the vehicle structure. Aluminum car frame ASF become a research hotspot. Aluminum joint deformation and damage which acts on the vehicle safety-critical failure to need for careful in-depth study.Therefore, the main study of this paper is the preparation and characterization of mechanical properties of welded joints of 2A12 Aluminum Alloy . Analyzed the stress phase of joints in different deformation and fracture behavior, access to the joint in tension, shear and mixed with a form of stress phase and fracture morphology of the fracture characteristics and the finite element technique and the uneven deformation joints initial damage was simulated.Throughout the material characterization , using the traditional method of hardness test and metallographic observation is the fusion zone of welded joints to determine the weakest area at first, then use the direct method is through the joint horizontal and vertical joints smooth access to micro-tensile mechanical properties .Then combined with micro-finite element simulation of stamping experiment indirectly joint mechanical properties of each region, through a comparative study of both the advantages and disadvantages. On this basis, through the notch tensile tests were welded butt joints under different stress and deformation and fracture mode of the fracture surface characteristics: smooth tension found in the state, the joints along the fracture surface are intergranular fracture, while in the pure shear stress fracture occurs when the joint shear relatively smooth muscles, are ductile fracture. In the mixed stress fracture occurs when the joint of the few large, shallow dimples in the dimple-like ray florets appear around the cleavage fracture. That the stress phase in different forms in different joint fracture, while using ABAQUS finite element simulation results verify the correctness of this. Experimental study of the failure analysis of welded joints to provide a theoretical basis.