| This paper discusses the preparation and properties of steel/aluminum/magnesium composite boards.Preparation of steel/aluminum/magnesium composite panels by hot rolling,and steel/aluminum/magnesium composite panels prepared by metallographic microscope,microhardness tester,tensile tester,scanning electron microscopy,and energy spectrometer.Perform organizational performance studies.Rolling temperatures were 300°C,350°C,400°C,450°C,and 500°C,and rolling reductions were 30%,35%,40%,45%,and 50%.The results show that the composite plates prepared in this process range can achieve good combination,and the composite plate prepared under the conditions of 450°C and 45% rolling has the best bonding effect.The bonded interface of the steel/aluminum layer in the prepared composite plate is tightly combined under the above rolling conditions and presents a flat straight line;the bonding surface of the aluminum-magnesium layer exhibits a wavy line,and the rolling reduction and rolling rate The increase of temperature undulates the wavy lines and increases the thickness of the bonding interface.The ratio of the deformation of the aluminum layer in the composite plate to the deformation of the magnesium layer increases with the rolling temperature and decreases with the rolling reduction.In the composite plate,element diffusion occurs during the rolling process of the steel/aluminum and aluminum/Magnesiu-m interfaces.With the increase of rolling reduction and rolling temperature,the thickness of the diffusion layer increases.The dynamic recrystallization of the magnesium layer in the composite sheet occurs.As the rolling temperature increases,the magnesium grains gradually become larger.With the increase of the rolling reduction,the grains appear to be refined and then become larger.Analysis of composite plate scanning fractures shows that the steel layer is ductile fracture;at low temperature and low pressure,magnesium/aluminum is ductile fracture;under high temperature and high pressure,the quantity changes into brittle fracture.In the given rolling temperature range,the tensile strength,yield strength,and elongation of the composite plate all increase first and then decrease.The bonding strength between steel and aluminum layers increases with the increase in reduction and temperature;the bonding strength between aluminum and magnesium layers increases first and then decreases with temperature and pressure reduction.With the increase of rolling reduction,the hardness of steel/Aluminum/magnesium layers at different positions continuously increases;with the increase of rolling temperature,the hardness at different positions of steel/aluminum/magnesium layers decreases gradually.The annealing treatment has a significant effect on the magnesium layer structure of the composite plate,the hardness of the aluminum-magnesium layer,the bonding strength of the aluminum-magnesium layer and the tensile strength of the composite plate.When the annealing temperature is between 0 and 200°C,the grains grow from the hot-rolled state into equiaxed grains.At 200°C to 350°C,the equiaxed grain grows further;during the period from 0 to 200°C,the grains grow.The materials are mainly solid-solvent compounds,which increase the bonding strength of the aluminum-magnesium layer;at 200°C to 350°C,the products are mainly brittle compounds,which leads to a decrease in the bonding strength;and the composite sheet is annealed at 200°C for 1 hour.Tensile strength and elongation have been improved. |
