Numerical And Experimental Research On The Magnetic Pulse Driving Elastic Medium Bulging Of 6061 Aluminum Alloy Sheet

In recent years,in response to the call of the state to take the road of sustainable development of environmental protection and ecology,researchers put forward the concept of lightweight and constantly promote the development of lightweight technology.As one of the representatives of light alloy materials,aluminum alloy is more and more widely used in automobile manufacturing industry and aerospace field.However,the problems of low plastic strain ratio,high springback,small Young’s modulus,high processing difficulty and poor form ability at room temperature restrict the development of lightweight aluminum alloys.This paper selects 6061 aluminum alloy plate as the research object.Study whether magnetic pulse technology and soft die forming process coupling can effectively improve the form ability of aluminum alloy.It provides a solid theoretical foundation for further exploration and application.The 2D electromagnetic structure model of 6061 aluminum alloy plate with magnetic pulse free expansion was established by ANSYS multi-physical field finite element analysis software.Analyze the distribution of magnetic flux density,magnetic field force and magnetic field lines on the drive plate.Obtain the forming process of 6061 aluminum alloy sheet under different discharge energy,The deformation law of plate deformation velocity,bulging height and wall thickness profile is analyzed.It provides theoretical guidance for experimental research.The magnetic pulse coupled elastic particle medium was used to study the thermal free swelling test of 6061 aluminum alloy plates.The results showed that:(1)When discharge energy is the only variable,the forming height of free expansion of aluminum alloy sheet increases with the increase of discharge energy.When the discharge energy is 7.0KJ,the forming height of free bulging of aluminum alloy plate reaches the maximum value,in which the bulging height at room temperature is 8.10 mm,the wall thickness is 0.837 mm,and the maximum principal strain value is 6.91%.(2)When the temperature change is the only variable,the forming height of free expansion of aluminum alloy sheet shows a trend of first increasing and then decreasing.When the temperature is set to 150℃,the temperature softening effect is obvious,and the maximum swelling height and strain value of the plate are significantly improved.When the discharge energy is 7.0KJ,the free expanded aluminum alloy sheet reaches the maximum forming height of 11.02 mm,wall thickness of 0.767 mm,and maximum strain value of 14.85%.(3)When the discharge number is the only variable,the forming height and strain of the secondary impact sheet bulging is better than that of the primary impact sheet bulging.Among them,the maximum forming height of free expansion of secondary impact aluminum alloy sheet under 7.0KJ energy is 11.38 mm,the principal strain value is 12.85%,and the wall thickness is 0.79 mm.The result of free bulging of the secondary impact aluminum alloy sheet is far superior to that of the next impact sheet under the same condition,which indicates that the free bulging of the multiple impact sheet is beneficial to improve the plastic deformation performance of the 6061 aluminum alloy sheet.(4)The numerical simulation and test results of free swelling of 6061 aluminum alloy plates driven by magnetic pulse coupled elastic particle medium are compared and analyzed.It is found that the swelling height and wall thickness of the plate are basically consistent.When the discharge energy is 7.0KJ,the bulging height of the tested and simulated plates is 8.10 mm and 9.11 mm respectively,and the wall thickness is 0.837 mm and 0.720 mm respectively.