Research On The Simulation And Prediction Of The Deep Drawing Process Of AZ31Magnesium Alloy Sheet Based On Dynaform

Since the1960s, the experts and scholars all over the world devoted to the theory study of finite element method and application, because it provides a strong analysis tool for the forming of material. Along with the rapid development of computer technology, there appear a large number of software based on the finite element method, and these kinds of software play more and more important role in practical projects. With the application and development of finite element numerical simulation technology, efficiency, economy and reliability of the FEA (Finite Element Analysis) software are gradually getting the eyes of researchers.This article is based on the special sheet metal forming FEA software ETA/DYNAFORM, the deep drawability of the AZ31magnesium sheet metal has been studied by numerical simulation. The most important parameters that influence the deep drawability are obtained through the uniaxial tensile test, such as the strain hardening exponent of the sheet metal n value and the normal anisotropic coefficient r value; and also the true stress-strain curve of the material under different temperatures obtained at the same time. Through the numerical simulation of the warm deep drawing test of the cylinder part, suitable process parameters were obtained for magnesium alloys sheet metal at different temperatures in deep drawing; The stress-strain state of the sheet metal during the deep drawing was analyzed combined with the simulation results, and the process possible defects based on the analysis results of the material in deep drawing and the prevention measures proposed; The deep drawing result by numerical simulation and experiments were compared.The results under existing condition show that:(1) The suitable forming process parameters for AZ31magnesium alloy sheet metal of1mm thickness are:the temperature is between150℃and170℃; The punch round radius is7mm or so, the fillet radius of the concave die is between7and11mm; the clearances between the drawing punch and die is1mm to1.75mm; the clearance between the binder and die is1.0mm to1.3mm;(2) The AZ31magnesium alloy sheet metal forming defects are predicted through the numerical simulation analysis in deep drawing process. The comparison between the experiments and the numerical simulation showed that, the two are in very good consistency.(3) There is no wrinkle when the cylindrical internal strain state is biaxial. The cylinder will wrinkle easily if the strain major in compressive strain state. From the analysis of material flowing and stress we learn that the internal stress of the cylinder depend on material flowing, where the material flow fast, there is stress concentration, and the tubular mouth is the most obvious stress concentration part.In short, there are lots of factors impacting the formability of AZ31magnesium alloy sheet. Using the FEA software to study the influencing mechanism of the factors and the forming conditions of the sheet is superior to other methods.