Numerical Simulation And Experimental Study On Rolling Process Of ZK60 Magnesium Alloy

As the lightest metal structural material,magnesium alloy has great application prospects in automobile manufacturing,national defense and military industry and highprecision electronics.Rolling production of magnesium alloy has the advantages of energy saving and high efficiency.It can also refine the material structure and significantly improve the product performance index.However,magnesium alloy rolling process still faces many technical problems,such as difficulty in accurate control of rolling temperature,serious texture phenomenon and low yield,which have become the main reasons restricting the mass production and wide application of magnesium alloy products.Therefore,taking ZK60 magnesium alloy as the research object,this paper carries out the finite element simulation analysis and hot rolling experiment of ZK60 magnesium alloy hot rolling process,focusing on the temperature change law of magnesium alloy plate during rolling process and the influence of process parameters on the microstructure evolution and mechanical properties of magnesium alloy plate.Firstly,the thermal compression simulation experiment of ZK60 magnesium alloy was carried out by Gleeble-3800 thermal simulation testing machine,the rheological stress curve of the material was obtained,and its thermal deformation behavior was analyzed.Based on the theory of hot working diagram,the hot working diagram of ZK60 magnesium alloy is established,and the reliable range of hot working process parameters of ZK60 magnesium alloy is determined.Secondly,the heat transfer coefficient of ZK60 magnesium alloy is studied by experiment and finite element simulation.The air cooling experiment of ZK60 magnesium alloy was carried out,and the convective heat transfer coefficient between ZK60 magnesium alloy plate and the surrounding air environment was solved by using deform reverse heat transfer module.The hot rolling experiment of magnesium alloy and finite element simulation analysis under the same working condition were carried out to determine the contact thermal conductivity between ZK60 magnesium alloy and roll.Based on finite element simulation analysis software MSC Marc established a twodimensional finite element model of ZK60 magnesium alloy rolling,and verified the reliability of the model through experimental data.The effects of rolling reduction rate,rolling speed,roll temperature,roll diameter and rolling temperature on the temperature change law of magnesium alloy rolling process are systematically studied.The heat transfer mechanism in the process of plate hot rolling is analyzed,and the specific process parameters for improving and optimizing the temperature in the deformation zone are obtained,which provides a theoretical basis for the reasonable formulation of process parameters and the prediction and control of temperature in the process of magnesium alloy plate hot rolling.Finally,the hot rolling experiment of ZK60 magnesium alloy was carried out in this paper.Through the methods of microstructure characterization and tensile property test,the effects of pass deformation,rolling temperature and rolling path on the microstructure evolution law and mechanical properties of ZK60 magnesium alloy were studied,and the optimization of rolling path on the base texture of rolled plate was evaluated.Compared with unidirectional rolling,cross rolling can significantly weaken the base texture and improve the anisotropy of rolled plate.