Diffusion Thickness And Heat Transfer Performance Of Cu-Al Composite Plate Under Service Condions

Cu/Al composite plate is an excellent conductive thermal conductivity composite,widely used in the fields of electronics,electrical appliances,machinery,automobiles and architecture.Cu/Al composite plate combined with interface stability has a direct impact on the use of composite board,under different service conditions,the interface layer of the Cu and Al has practical value.In this paper,the Cu/Al composite plate is prepared by cast-rolling method and subjected to study in different simulated working environments.The morphology and phase of the interface layer and the peeling surface are observed and tested by SEM,EDS and XRD,when the composite plate is used as conductive,low-temperature heat transfer,and high-temperature heat transfer materials respectively;Flash method was used to measure thermal diffusivity and thermal conductivity of the Cu/Al composite plate at temperatures ranged from 50 to 300℃,selected three Cu/Al thickness ratios:1:1,1:2,and1:3,values of thickness and temperature of Cu/Al Layert on the thermal conductivity of composite plate was analyzed;Using ABAQUS simulation software to establish a heat transfer calculation model of composite plate.And the thermal conductivity of composite plate was calculated under different copper and aluminum layer thickness and temperature conditions.By comparing the simulation results with the experimental measurements of the flash method,the reliability of the calculation model is verified.The findings indicate that:The thickness of the diffusion layer showed an increasing trend when the Cu/Al composite plate is in service at 70℃,100 ℃,150℃,200℃,and 300℃.Under the service conditions of 70℃,100℃,and 150℃,the interfacial layer thickness increases rapidly at first,then slowly,and the increasing trend is small,eventually tends to be stable;Under the service conditions of 200℃ and 300℃,when the heating time reaches 72 hours,the diffusion layer thickness increases rapidly first and then the growth rate decreases.The thickness ratios of copper and aluminum were 1:1,1:2 and 1:3,and the thermal conductivity decreases with the increase of working temperature.With the increase of the thickness of aluminum layer,the overall thermal conductivity of Cu/Al composite plates decreases step by step.The thermal conductivity of composite plates of the same thickness decreases with the increase of service temperature.With the thickening of the diffusion layer of the composite interface,the scattering of electrons by solid soluble atoms andintermetallic compounds generated in the diffusion layer increases,and then the thermal resistance of the composite plate is increased and the thermal conductivity is reduced.The simulation results are obtained by ABAQUS,and the thermal conductivity of the Cu and Al ends of the simulated cast Cu/Al composite plate is similar to the experimental results.With the increase of aluminum layer thickness,The experimental and simulation values of the composite thermal conductivity of Cu/Al composite plates are gradually reduced,so the simulation results have the same trend as the experimental results.