Efect of high temperature and high strain rate on the dynamic mechanical properties of Fe-30Mn-3Si-4Al TWIP steel

Zhi-ping Xiong^1,2，Xue-ping Ren¹，Wei-ping Bao³，Jian Shu¹，Shu-xia Li¹，Hai-tao Qu¹

1. School of Materials Science and Engineering, University of Science and Technology Beijing2. School of Mechanical, Materials and Mechatronic Engineering, University of Wollongong3. School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing

摘 要：The dynamic mechanical properties of Fe-30Mn-3Si-4Al twinning induced plasticity（TWIP） steel were studied by the split-Hopkinson pressure bar（SHPB） at temperatures of 298-1073 K and strain rates of 700,2500,and 5000 s-1.The TWIP steel indicates strain rate hardening efect between 700 and 2500-s 1,but it shows strain rate softening efect between 2500 and 5000-s 1.In addition,the strain rate softening efect enhances with an increase in deformation temperature.After deformation,the microstructures were studied by optical microscopy（OM）.It is shown that the deformation bands become more convergence,a part of which become interwoven with an increase in strain rate,and the dynamic recovery and recrystallization are enhanced with an increase in both temperature and strain rate.

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