Numerical Simulation Of Casting Process For 6005A Aluminum Alloy Used In Rail Transit

In recent years,aluminum alloy,especially aluminum 6005A with its excellent strength,weldability and extrudability at home and abroad has been widely used in transportation.However,aluminum alloy ingot made out of semi-continuous casting method has more coarse grains and columnar crystals that have more prone to produce cracks and other defects.To solve this problem that gets the excellent quality of aluminum ingot,this thesis mainly through the addition of low frequency electromagnetic fields,change the casting parameters,the shunt system and other methods to obtain a uniform fine grain 6005A aluminum ingot.This method also provide technical support with aluminum production.To understand impacts on all macroscopic physical fields of the additions of low frequency electromagnetic fields and changes in casting conditions,commercial finite element software ANSYS and CFD software FLUENT are used to establish a more suitable to LFEC and DC two processes flow and temperature fields and electromagnetic fields mathematical model of the interaction of physical field coupling.The use of established mathematical model calculate the(1)582mm aluminum 6005A DC and LFEC process.Then the simulation results are compared with the experimental results.The results of two methods are basically the same.So the simulation results are more reasonable and accurate.By numerical simulation analyzes,the impact on flow field,temperature field,sump and solidification front velocity of the low frequency electromagnetic fields of ?582mm aluminum ingot during LFEC casting process are studied.And analysis the influence of different casting conditions in LFEC process,such as casting speed,casting temperature,current strength,the secondary cooling zone wiper whether to add.Also the influence of different shunt methods in casting process are studied.Simulation results show that the low-frequency electromagnetic field will produce Lorentz force.The aluminum alloy melt forced convection,speed up the flow velocity and change flow direction,promote aluminum heat melt speed to prevent overheating of molten aluminum alloy phenomenon,the temperature more uniform distribution within the ingot,sump lighter will happen in the action of Lorentz force.Meanwhile electromagnetic solenoid mold caused agitation near the solidification front speed,is conducive to the uniform solidification structure refinement.The multi-point for shunt flow can make in the entire ingot aluminum solute distribution and tends to melt aluminum original solute concentration,to prevent the occurrence of negative segregation ingot casting center and get a better quality of aluminum ingot.