High Temperature Deformation of a Structural Steel
The mechanical behavior of a fire resistant steel was studied by means of tensile tests performed in the temperature interval from 25 to 600oC, at strain rates from 10-4 to 10-2 s-1, aiming at analyzing the role of alloying elements in the dynamic strain aging (DSA) phenomena occurring in this steel. Typical features of DSA were observed: serrated flow (the Portevin-LeChatelier – PLC effect), the presence of a maximum and a minimum in ultimate tensile strength and elongation versus temperature curves, respectively and a plateau in yield strength versus temperature curves. Apparent activation energies were calculated based on the onset of PLC effect and the maximum in ultimate tensile strength. Results suggest that changes in mechanical properties associated with DSA in the fire resistant steel are related to the dynamic interaction of C-substitutional dipoles and dislocations.
S.-J.L. Kang, M.Y. Huh, N.M. Hwang, H. Homma, K. Ushioda and Y. Ikuhara
B.M. Gonzalez et al., "High Temperature Deformation of a Structural Steel", Materials Science Forum, Vols. 558-559, pp. 1383-1388, 2007