Experiment And Microstructure Evolution Simulation Of Lead Alloy Prepared By Roll-casting With A Combination Energy Field Of Electromagnetic And Ultrasonic

Two-roll continuous roll-casting is a kind of short process technology with low investment, high energy saving, that is considered to be a petential near net shape technology to production of sheet metal. It has a lot of advantages, such as: high rate of finished product, less pollution, low investment, high production and so on. But the plate produced by this method with severe coarse grain and serious composition segregation, these defects will effect the properties of lead alloy plate. There, basisd on the general continuous cast-rolling of lead alloy strip, a combination of electromagnetic and ultrasonic field has been introduced to the process and roll-casting with a combination of electromagnetic and ultrasonic field was realized.In this paper, according to the actual casting process, has analysis the heat transfer boundary conditions of the casting process, and construction of Pb-Ag alloy thermo physical parameters, finally based on the ProCAST lead alloy electromagnetic ultrasonic roll-casting microstructure simulation model was established. The relationship between different process parameters and microstructure has been researched. The results show that the electromagnetic ultrasonic energy field can be refined lead alloy strip microstructure, and with the electromagnetic ultrasonic energy field intensity increased thinning effect is enhanced, the reasonable pouring temperature is340℃-360℃, the reasonable casting speed is1.Om/min～1.4m/min.Under the guidance of simulation process parameter a lot of lead alloy electromagnetic ultrasonic roll-casting experiment was done, the microstructure of lead alloy roll-casting strip with electromagnetic and ultrasonic was observation and analysis using an optical microscope and EDS, and the mechanical properties of lead alloy strip was tested. Finally the reasonable parameters of preparation lead alloy strip with electromagnetic and ultrasonic was obtained, good performance of the lead alloy strip can be got when casting speed is1.0m/min-1.4m/min; the pouring temperature is340℃-360℃; excitation current is10A; ultrasonic power is200-300W. Lead alloy strip metallographic observation shows that, after the electromagnetic and ultrasonic energy field processing, lead alloy plate with tissue from more developed grain into fine grains, tissue becomes uniform, grain size decreased from100μm-120μm to 60μm～80μm, which verified the effect of technological parameters on the microstructure got by simulation. The mechanical properties test results certify the tensile strength, yield strength, elongation and hardness of the combination energy field roll-casting lead strip are increased by12.42%,29.17%,24.16%and1.7%than that of the general cast-rolling lead strip.