Abstract
An ultra-low carbon acicular ferrite steel heavy plate was obtained with an advanced thermo-mechanical control process-relaxed precipitation controlled transformation (TMCP-RPC) at Xiangtan Steel, Valin Group. The heavy plate has a tensile strength of approximately 600 MPa with a lower yield ratio. The impact toughness of the heavy plate achieves 280 J at −40°C. The fine-grained mixed microstructures of the heavy plate mainly consist of acicular ferrite, granular bainite, and polygonal ferrite. The high strength and excellent toughness of the heavy plate are attributed to the formation of acicular ferrite microstructure. The prevention of blocks of martensite/retained austenite (M/A) and the higher cleanness are also responsible for the superior toughness.
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This work was financially supported by the National Natural Science Foundation of China (Nos.50471107 and 50734004).
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Cao, Zq., Bao, Yp., Xia, Zh. et al. Toughening mechanisms of a high-strength acicular ferrite steel heavy plate. Int J Miner Metall Mater 17, 567–572 (2010). https://doi.org/10.1007/s12613-010-0358-9
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DOI: https://doi.org/10.1007/s12613-010-0358-9