Deformation Behavior and Microstructure of Low Carbon High Manganese Steels in Tensile Strain
The mechanical properties of two high manganese steels with manganese contents (15% and 25%) were investigated during tensile tests at room temperature. The results indicated that the strengths of steels were a little low and the elongations were improved greatly with increasing the manganese content. Stress fluctuations were found during tensile tests of the Fe-15Mn steels, and as the strain increased the range of stress fluctuations became wider. The strain hardening exponent n of samples changed with strain in a parabola model. The microstructures before and after deformation were investigated and the results showed that phase transformation of γ (fcc) →ε (hcp) and γ (fcc) →ε (hcp) →α (bcc) induced plasticity occurred in the Fe-15Mn steels. However, in the Fe-25Mn steels, at the beginning stage of the deformation, phase transformation induced plasticity played an important role, and with the increase of deformation, the main mechanism was twinning induced plasticity.
Hyungsun Kim, JienFeng Yang, Tohru Sekino and Soo Wohn Lee
L. L. Wang et al., "Deformation Behavior and Microstructure of Low Carbon High Manganese Steels in Tensile Strain", Materials Science Forum, Vols. 620-622, pp. 335-338, 2009