The Mechanical and Deformation Behavior of TWIP Steel Prepared by Directional Solidification

Abstract:

A directionally solidified TWIP steel (Fe-25Mn-2.5Al-2.5Si) was prepared by liquid metal cooling technology. The microstructure and mechanical behavior were examined and compared with usually solidified samples. The directionally solidified TWIP steel shows a typical columnar grain structure, and the maximum true stress and true strain along the longitudinal direction of the sample are 1060MPa and 71% respectively. As a comparison, the usually solidified samples shows an equiaxed grain microstructure with the maximum true stress and true strain of only 994MPa and 58%, respectively. Moreover, the two solidification modes also lead to very different strain hardening behavior, particularly in the changes of strain hardening rate with strain. This suggests that the grain boundary plays a key role in the mechanical properties of TWIP steels, and changing the grain boundaries can be effective to improve the comprehensive mechanical properties of TWIP steels.

• Periodical: Materials Science Forum (Volumes 783-786)
• Pages: 761-765
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.783-786.761
• Online since: May 2014
• Authors: Dan Wang*, kun wang, Zi Mu Shi, Fu Sheng Han
• Keywords: Directional Solidification, Mechanical Property, Plasticity, TWIP Steel

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