Simulation Of Rolling Process And Technical Study On Steel/Aluminum/Aluminum Alloy Laminated Plates With Corrugated Interface

Steel/aluminum clad plate combines the advantages of high strength and toughness of steel,light weight,strong corrosion resistance and good thermal conductivity of aluminum.It is widely used in shipbuilding,transportation,petrochemical and other fields.In order to solve the problems of uncoordinated deformation,interfacial oxidation and low bonding strength in the rolling process of steel/aluminum clad plates,a new rolling method of "prefabricating corrugation by cold rolling and flat roll leveling by hot rolling" for steel/aluminum clad plates was proposed.The effects of different process parameters on the properties of prefabricating steel/aluminum corrugated clad plates were studied by means of finite element simulation and experiment.The influence mechanism of different prefabricating corrugation processes on the interface of steel/aluminum/aluminum alloy laminated plates was studied.And the effects of reduction rates of flat rolling on mechanical property and interfacial structure of steel/aluminum/aluminum alloy laminated plate were analyzed.Firstly,using ABAQUS finite element simulation software to set up a two-dimensional finite element model of steel/aluminum clad plate by cold rolling.And the reliability of the model was verified.Based on the established model,the effects of reduction rates of corrugated rolling,heat treatment temperature of aluminum strip before rolling and rolling speed on the interfacial deformation of steel/aluminum corrugated clad plate were studied.And the variation of positive stress,shear stress and equivalent strain at the interface were predicted.Secondly,the related experimental study was carried out on the basis of finite element simulation.The effects of different reduction rates and heat treatment temperatures of aluminum strip before rolling on the surface quality and interfacial morphology of the steel/aluminum corrugated clad plate were studied.The result shows that there is an optimal reduction rate in the process of prefabricating steel/aluminum corrugated clad plates.If the reduction ratio is too small,it is not easy to combine,and if too large,the aluminum layer will break by corrugated roller.It draws a conclusion that 20% average reduction rate of corrugated rolling can make the aluminum strip cover the surface of steel plate and prevent high temperature oxidation from the interface of steel and aluminum.The increase of heating treatment temperature of aluminum before rolling leads to the increase of aluminum layer ductility and the decrease of deformation resistance,which is more conducive to the interfacial bonding of steel/aluminum clad plates.Thirdly,the mechanical performance and interfacial morphology of the steel/aluminum/aluminum alloy laminated plates were studied.It shows that the interfacial shear strength of steel/aluminum/aluminum alloy laminated plates can attained 77.68 MPa in rolling direction and 92.63 MPa in transverse by optimizing prefabrication process,and the interfacial bonding strength is much higher than the related standards 55 MPa.And the steel/aluminum/aluminum alloy laminated plate realizes the mechanical occlusion and metallurgical bonding between the layers.Finally,the effects of reduction rates on mechanical property and interfacial morphology of steel/aluminum/aluminum alloy laminated plate were studied.The result shows that when the reduction rate of flat rolling is between 35% and 50%,with the increase of reduction rate,the tensile strength of the clad plate increases,the elongation and the defects of bonding interface of the clad plate decrease gradually.The thickness of interfacial diffusion layer is basically the same.But the bonding strength of the laminated plate first increases and then decreases.Subsequently,the steel/aluminum/aluminum alloy laminated plates were annealed at400?,500? and 600? for 1 h respectively and then air-cooled.It is found that the shear strength decreases when the laminated plate annealed at 400? and 500? for 1 h respectively,compared with the non-annealed laminated plate,but still higher than the national standard.However,when the laminated plate annealed at 600? for 1 h,the interface of the laminated plate cracked directly.The research result confirmed the feasibility of the new rolling method of "prefabricating corrugation by cold rolling and flat roll leveling by hot rolling" for steel/aluminum/aluminum alloy laminated plates.It provides a new idea for improving the interfacial bonding strength of steel/aluminum clad plate.