Wrought Magnesium Alloy Sheet Rolling Temperature And Edge Cracking Studies

Wrought magnesium alloys have characteristic of low density and highspecific strength, which rolled sheet is widely used in aerospace, automotive,shipbuilding and other important industry, and it will be a new material whichcan replace of steel in some areas in the future. However, at room temperature,the base surface’s slip numbers of magnesium alloy does not meet the von misescriterion, then, it can be mold difficultly. and in the hot rolled condition,temperature factors such as thermal radiation, convective heat transfer, contactheat transfer between roll and Mg sheet, friction heat, Plastic deformation heatand so on. Moreover, alternating tension and compression stress of roll impacton Mg sheet, these can lead to rolled edge cracks, this paper studies influence ofabove factors on hot-rolled Mg sheet, in order to establish mathematical modelof temperature field of hot-rolled Mg sheet and mathematical model of cracks’stress.Plastic finite element numerical simulation method is a widely applicablemethod for various boundary issues, it is combined energy equation withvariational principle, effects of hardening and metal’s forming characteristics.By setting parameters of finite element software to predict the effects onforming workpiece, and internal microstructure changes are simulated duringforming process, it has some significance on controlling evolution ofmicrostructure of actual process.Firstly, cast rolled AZ31B magnesium alloy sample is compressed byGleeble-1500D thermal deformation simulator under different temperature andstrain rate, its stress-strain data is processed by linear regression to establishAZ31B magnesium alloy’s hot deformation constitutive equation, peak strainequation, kinetics mathematical model of dynamic recrystallization, moreover,each mathematical model is verificated.Secondly, Based on factors such as heat transfer of radiation, heat transferof convective, friction heat between Mg sheet and roll, heat of plasticdeformation, thereby AZ31B magnesium alloy sheet’s mathematical models are established, Which are rolling temperature drop mathematical model,mathematical model of temperature field along sheet’s width direction,mathematical model of air-cooled state and cracks’ stress.Using Deform-3D numerical simulation software to simulate which rolledMg sheet under different conditions, Mg sheet’s edge damage and temperaturedistribution are observed, and using Deform-3D’s microstructure module,accessing points on the central and edge of magnesium sheet to simulateevolution of internal grain, It can make quantitative research.Studies on factors impacted on microstructure and mechanical properties ofcast rolled AZ31B Mg alloy sheet, and then reducing quantity of internalstratification dendrites, Mg17AlZn12and brittle phase aboutMg2Si. which canrefine grain, analyzed of mechanical properties of cast rolled Mg sheet afterrolled and compared temperature drop and calculations by FEM.This article relies on a Luoyang copper enterprise’s project of rolled widewrought magnesium alloy, error between experimental results and numericalsimulation’s results is small, this study has some significance on the project.