Abstract：In order to investigate the effect of integrated austempering and Q&P(quenehing and partitioning) process on microstructure and mechanical properties of a medium-carbon high-strength bainitic steel,the microstructural observation,dilatometry,X-rays diffraction and tensile tests were utilized to clarify the microstructural evolution and property changes treated by integrated austempering and Q&P process. Results demonstrate that the integrated austempering and Q&P process can refine the blocky M/A islands and the coarse blocky M/A islands can be successfully converted to filmy austenite and carbon-depleted martensite plates. In addition,mechanical properties are enhanced by integrated austempering and Q&P process compared to that by austempering or Q&P process individually. Moreover,compared to austempering or Q&P process individually,more austenite with higher carbon content are retained through integrated austempering plus Q&P process.
刘曼, 胡海江, 田俊羽, 陈光辉, 徐光. 贝氏体钢等温淬火和淬火-配分复合工艺[J]. 钢铁, 2021, 56(1): 69-74.
LIU Man, HU Hai-jiang, TIAN Jun-yu, CHEN Guang-hui, XU Guang. Integrated austempering and quenching-partitioning process of a bainitic steel[J]. Iron and Steel, 2021, 56(1): 69-74.
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2021, Vol. 56 
