tailieunhanh - Determining the material model at elevated temperatures with different strain rates and simulating the warm forming process for Mg alloy AZ31B sheet

In this paper, the simulation of the hot forming process for Mg alloy AZ31B sheet is on PAM- STAMP2G software. Magnesium alloy is one of lightweight alloys has been studied more extensively today. | TAÏP CHÍ PHAÙT TRIEÅN KH&CN, TAÄP 18, SOÁ K4- 2015 Determining the material model at elevated temperatures with different strain rates and simulating the warm forming process for Mg alloy AZ31B sheet Truong Tich Thien Nguyen Thanh Long Vu Nguyen Thanh Binh Nguyen Thai Hien Ho Chi Minh city University of Technology, VNU-HCM (Manuscript Received on August 01st, 2015, Manuscript Revised August 27th, 2015) ABSTRACT: Magnesium alloy is one of lightweight alloys has been studied more extensively today. Because weight reduction while maintaining functional requirements is one of the major goals in industries in order to save materials, energy and costs, etc. Its density is about 2/3 of aluminum and 1/4 of material used in this study is commercial AZ31B magnesium alloy sheet which includes 3% Al and 1% Zn. However, due to HCP (Hexagonal ClosePacked) crystal structure, magnesium alloy has limited ductility and poor formability at room temperature. But its ductility and formability will be improved clearly at elevated temperature. From the data of tensile testing, the constitutive equations of AZ31B was approximated using the RamgbergOsgood model with temperaturedependent parameters to fit in the experiment results in tensile test. Yield locus are also drawn in plane stress 1 2 with different yield criteria such as Hill48, Drucker Prager, Logan Hosford, Y. W. Yoon 2013 and particular Barlat 2000 criteria with temperaturedependent parameters. Applying these constitutive equations were determined at various temperatures and different strain rates, the finite element simulation stamping process for AZ31B alloy sheet by software PAM- STAMP 2G 2012, to verify the model materials and the constitutive equations. Key words: Magnesium alloy sheet, AZ31B, constitutive equation, strain hardening, Ramgberg- Osgood, Barlat 2000, finite element method. 1. INTRO DUCTIO N Magnesium alloys are increasingly becoming the ideal materials for modern industrial .