Influence of Rapid Cooling Temperature on the Microstructure and the Mechanical Properties of a High Al Dual Phase Steel

Abstract:

Annealing process with different rapid cooling temperatures of a hot-dip galvanized high Al dual phase steel was simulated by hot-dip process simulator (HDPS). The results indicated that the tensile strength of the samples increased and the elongation decreased slightly with the increase of rapid cooling temperature from 460 °C to 520 °C. When the rapid cooling temperature was higher than 500 °C, the tensile strength was more than 605MPa, and the elongation rate reached to 32%, the samples was found to have better mechanical properties. It was found by transmission electron microscope (TEM JEM2100F) that the microstructures of the samples were mainly composed of ferrite, island martensite and retained austenite when the rapid cooling temperature was higher than 500 °C, and when this temperature was lower than 480 °C, some island martensites were tempered and carbide was appeared in the island phase.

• Periodical: Advanced Materials Research (Volumes 311-313)
• Pages: 845-849
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.311-313.845
• Online since: August 2011
• Authors: Zhao Jun Deng, Jing Liu, Hui Wang, Cheng Jiang Lin, Zhi Hong Lu
• Keywords: Dual Phase Steel, Island Phase, Rapid Cooling Temperature, Tensile Strength

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