| Automotive Lightweight Technology for automobile industry to realize energy saving and emission reduction,is of great significance to realize the sustainable development of car body.The multi material mix can effectively realize the lightweight car,but also improve the safety performance of aluminum steel composite structure.As a kind of composite structure commonly used in welding difficulty,the magnetic pulse welding process can effectively solve this problem.In this paper,aluminum-welded joint of high strength steel are carried out to evaluate the performance of all parameters and multi process test environment,the welding application structure in aluminum and steel to provide a reference for magnetic pulse.(1)ANSYS Maxwell electromagnetic finite element analysis platform based on type E coil are analyzed the transient electromagnetic field,analyzes the distribution and its variation in different excitation current under the current density and magnetic field strength,the dynamic analysis of the electromagnetic force of different size of welding coil driving.The welding work coil section is small,while the magnetic field intensity is higher,the better the effect in magnetic driving ability,the more strong,can obtain good welding effect is expected,but the small section will bring large current loss and heat effect,coil life.The ultimate combination of service life and the effect of welding two a section of the larger the welding coil selection,according to the post test,the welding effect is good.(2)The parameters of multi energy spacing welding test was carried out with 5052 Aluminum Alloy-HC420LA high strength steel welding,quasi-static tensile properties of welded joints at room temperature are tested,analyzed the effects of welding parameters on the welding quality,found in each energy corresponds to multiple weld spacing to obtain the best welding process with the development of welding parameters,and the energy boost,impact speed,realize the parent material fracture of welded joints were greatly improved.By means of microstructure analysis comparative analysis of the different failure modes of welding of aluminum and steel,welding and welding related failure found the collision speed.The weld width smaller form smaller velocity and larger velocities that forms at the interface of metal compounds and micro cracks and voids.(3)Through simulation tests under different environmental conditions,to further improve the evaluation system to the joint welding of aluminum steel.The tensile test at different rates based on the discovery with strain rate sensitivity of certain aluminum steel welded joints,but its sensitivity is lower than that of the base material 5052 Aluminum Alloy,the high-speed stretch,while welding the joint strength has been improved,but the failure modes are Weld Fracture of aluminum steel;welding high temperature cycle test,found after 3 cycles of the mechanical properties decreased to some extent,but the effect of cycle number is lower than the effect of cooling method.Through microscopic analysis,found that the welded joint of air cooling and the water appeared micro cracks,which lead to the performance degradation of aluminum and steel;mechanical properties of welded joints in the salt fog corrosion environment degradation is very obvious,the corrosion from the first weld tip To start,this is due to the weld tip density not good cause.At the same time in welding and Aluminum Alloy under the condition of low degree,electrical steel,accelerate the corrosion rate of the steel.So for aluminum and steel welding in actual service environment,must consider the anticorrosion design. |
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