Research On Microstructure Simulation And Properties Of Continuous Cast-rolling Lead Anode Plate

The lead alloy strips are widely used in the copper and zinc electrowinning, whose electrochemical and mechanical properties have direct impact on the energy consumption and the service life of anodes. In order to effectively reduce the energy consumption and increase the service life of anodes, there are a lot of research on the compositiones of lead alloys, but less on the molding process. It’s the first case that continuous cast-rolling method is used for the preparation of the lead anode plate. As we all know, cast-rolling is a very complex process, there are varieties of influencing factors in it. It’s difficult to find the matching relationship between the various process parameters simply through a number of experiments. In this paper, the finite element simulation is used to study the characteristics of solidification of cast-rolling lead anode plate and the impact of the change of process parameters on solidification structure. The simulation results were verified by practical experiments. The verification results show that simulation and experimental results are good consistency.The related properties of the lead anode plate prepared by continuous cast-rolling method were studied through the devices of Leica DMI5000M metallurgical microscope, JSM-6490LV scanning electron microscope, QJ19one-twinned brachial electric bridge, CSS-44100electronic universal testing machine, HW-187.5Brinell hardness tester and so on. Concrete work are as follows: I The finite element simulation theory of heat transfer, liquidity, the nucleation and growth are used to build the Temperature-Flow-Structure coupling finite element model of the solidification process of lead anode plate. The model was simplified through appropriate assumptions and then the boundary conditions of the simulation was determined.II The CAFE module in the Procast and Deform-3D was used to simulate and analyze the solidification structures of cast-rolling lead anode plate. The nucleation and growth of the lead alloy were the focus of the study. The impactes of cast-rolling speed and pouring temperature on the solidification structures were analyzed systematically, which provides the theoretical basis for both the optimization of the processing parameters and the control of the solidification structure and strip quality.Ⅲ Based on the results of finite element simulation analysis, the continuous cast-rolling experiments of lead anode plate were carried out. The microstructure and properties of roll casting quaternary Pb-Ag-Ca-Sr alloys before and after subsequent rolling were investigated through anodic polarization stable potential, corrosion rate, surface morphology before and after polarization, conductivity, tensile properties and hardness. The result show that:the corrosion resistance is1.48times as that of the original lead anode plate; the ultimate tensile strength σb and yield strength σp0.2increase by28.5%and79.4%, respectively; the hardness also increases2.8HBS.