Study On Process Parameters Interaction And Kiss Point Height Analytical Model Of Cu/Al Vibration Compound Cast-rolling

The twin-roll thin strip composite cast-rolling technology stands out because of its high efficiency,short process,and green characteristics in many processes of preparation of layered metal composite strip.However,this technology still has problems such as uneven structure of the strip,coarse grains,and low interface bonding strength,which seriously affects the service performance of the composite strip.In response to the problems,the research group proposed a new technology of vibration composite cast-rolling.The single-sided roll vibration produces a "stirring" effect on the molten pool area,which can achieve the refinement of the structure grains and the improvement of the interfacial bonding strength.The interface heat transfer coefficient between the roll surface and the molten pool is an important parameter in the vibratory composite cast-rolling process.It plays a key role in product performance by influencing the growth of the internal organization of the composite strip.Based on this,a solid-liquid contact heat transfer experimental platform was designed to measure the temperature changes during the contact between the 20CrMo specimen of the same material as the roll and the molten metal.The heat conduction inverse analysis method is used to solve the interface heat transfer coefficient between the 20CrMo specimen and the molten metal,which provides a theoretical basis for accurately simulating the heat transfer process between roll surface and molten pool.Kiss point,as a reference index to divide the cast-rolling molten pool into casting zone and plastic deformation zone,plays a decisive role in the stability of compound cast-rolling process.Considering that the vibration of roll will make the height of kiss point fluctuate,which will disturb the stability of cast-rolling process,a simulation model of vibration compound cast-rolling was established based on the finite element software.The interaction of process parameters and the influence of vibration conditions on the height of kiss point were analyzed.According to a large number of simulation data,the kiss point height analytical model with time domain characteristics was established,which lays a solid foundation for the industrial application of Cu/Al vibration composite cast-rolling technology.The Cu/Al vibration and non-vibration composite cast-rolling experiments were carried out on the ?500×350mm twin-roll vibration cast-rolling mill.The solidified molten pool tissue under non-vibration condition was obtained by the process of emergency stop process.After the section and the corrosion treatment,the metal eddy current trace and the solid phase line morphology were observed,and the accuracy of the simulation model was verified.The mechanical properties of the strips produced by vibration cast-rolling and non-vibration cast-rolling were compared.The results show that vibration can obviously improve the mechanical properties of composite strips,and the superiority of new technology of vibration composite cast-rolling was proved.