Hot Deformation Behavior of 980MPa δ-TRIP Steel

Abstract:

The δ-TRIP steel has attracted wide attention from researchers and industry, as it possesses the mechanical properties of the third-generation advanced automotive steels, and the lower density achieved by the addition of light element aluminum. However, there have been few studies on the hot deformation behavior of δ-TRIP steel at high temperature, which is critical for the design of the hot rolling process. In the present study, hot compression tests were carried out on a 980 MPa δ-TRIP steel to achieve a better understanding of the deformation behavior at high temperatures from 800°C to 1150°C. Combined with the electron backscatter diffraction (EBSD) analysis, the results showed that δ-TRIP steel was a positive strain-rate sensitive material, and its soften was contributed by dynamic re-crystallization of ferrite and austenite during deformation at high temperature. The hot deformation activation energy (Q = 327.485 kJ/mol) of the experimental steel was calculated, and the strain index was 5.65. Besides, the related constitutive equation and the flow stress equation were also established.

• Periodical: Materials Science Forum (Volume 1035)
• Pages: 368-376
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.1035.368
• Online since: June 2021
• Authors: Jian Fu, Peng Chen, Hong Liang Yi*
• Keywords: Activation Energy, Flow Stress, Hot Deformation, Re-Crystallization, δ-TRIP Steel

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