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Study on Austenitization Kinetics of SA508 Gr.3 Steel Based on Isoconversional Method
Xiaomeng Luo, Lizhan Han and Jianfeng Gu *
Keywords: isoconversional method; austenitization kinetics; SA508 Gr.3 steel; dilatometry; time-temperature-austenitization (TTA) diagram
Abstract: The austenitization kinetics of SA508 Gr.3 steel during heating was studied using the isoconversional method combined with continuous thermal dilatometric tests for the first time. The model-free austenitization kinetics was built and the effective activation energy as a function of transformed austenite fraction was determined without transformation models. Then, the corresponding regression validation was carried out. The time-temperature-austenitization (TTA) diagram of SA508 Gr.3 steel, which is very difficult to be obtained using experiment measures, was constructed. Finally, the austenitization kinetics in a more realistic case, i.e., under non-constant heating rates, was predicted, which is found to agree well with the experimental results.
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