Influence of Cooling Rate on the Microstructures and Properties of Q550

Abstract:

A Q550 high strength steel was selected at two different cooling rates through ultra-fast cooling process, and its microstructures and strengthening mechanisms were analyzed. The results show the bainite transformation temperature of the steel decreased with the increasing of cooling rate.The ultra-fast cooling process can improve the performance of Q550 compared with the conventional cooling process, and the yield strength, tensile strength and elongation are 600MPa, 755MPa and 19%, and - 20 °Cimpact energy is 253J, and good strength and toughness are obtained under ultra-fast cooling process. The microstructure of this steel is bainite and good strength and toughness are caused by the refinement of bainite and fine precipitates. Ultra-fast cooling technology improves the strength and toughness of this steel effectively.

• Periodical: Applied Mechanics and Materials (Volumes 117-119)
• Pages: 1705-1707
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.117-119.1705
• Online since: October 2011
• Authors: Fan Li, Hai Long Yi, Zhen Yu Liu, Guo Dong Wang
• Keywords: Bainite Transformation, Pecipitate, Strengthening, Ultra-Fast Cooling Process

References

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