Method And Device For Semi-solid Liquid Film Formation And Performance Test

Metal laminated composite materials are composed of many kinds of metals with different properties in a layered way,which can give full play to the performance advantages of each metal element,and has a broad development and application prospect.Cu-Al laminated composites have the advantages of light weight and low cost of aluminum and good electrical and thermal conductivity of copper,which can replace part of pure copper in heat dissipation and transmission equipment,thus saving precious metals.At present,the interfacial stability of copper/aluminum composite plates has attracted wide attention in practical application.In this paper,the liquid-solid semi-molten casting and rolling method is used to prepare Cu-Al composite plates.This method can effectively solve the oxidation problem between Cu-Al in Cu-Al composite plates.The microstructure and phase composition of the interfacial diffusion layer were studied by means of scanning electron microscopy(SEM),X-ray diffraction(XRD)and energy spectrum analysis(EDS).The solid-phase bonding process and the formation and evolution mechanism of the interfacial were analyzed.The interfacial bonding properties and the overall mechanical properties of the composite tape were studied by tensile test,interfacial peel test and microhardness test.The diffusion process and crystal structure of the diffusion layer were simulated by Material Studio,LAMMPS and OVITO.At 150?,200?and 250?for a long time,the interfacial diffusion layer increases with the heat treatment time,and the number of interfacial diffusion layer increases from two layers to three layers in cast and rolled state.When heated at150?,the interface of the composite plate is in a stable state,and the thickness of the diffusion layer increases slightly.At 200?,the thickness of the interface layer increases slowly within 100 hours,and the interface is in a stable state.However,when the holding time continues to increase,the interface becomes unstable.At250?,the thickness of the diffusion layer at the interface of the composite plate increases rapidly with the extension of heating time and has no slowing trend.The interface of the composite plate is unstable.Two interfacial layers are formed at the interface of cast-rolled composite plate,and?(Al₂Cu)phase is formed at the interface.With the effect of temperature during heat treatment,the intermetallic compounds formed in the diffusion layer are?₂(Al Cu),?(Al₂Cu)and?₂(Al₄Cu₉)when the diffusion layer is three layers.The respective crystal cells of copper and aluminum were established by Material Studio software to form the supercell structure,and the simulation results were obtained by LAMMPS calculation software.Finally,Ovito was used for visualization.Through the atomic structure,crystal structure change,root mean square,radial distribution function and other data of the diffusion layer,it is found that with the increase of heating temperature and time,the degree of diffusion becomes more intense.Therefore,the simulation results obtained from the experiment have the same variation trend as the experimental results.