Abstract
In this work, DIFT technology and Q&P process were combined in order to introduce ultrafine-grained ferrite into the matrix of martensite and retained austenite to develop a new kind of advanced high strength steel, and two kinds of steels were investigated by this novel combined process. The newly designed process resulted in a sophisticated microstructure of a large amount of ferrite(about 5 μm in diameter), martensite and a considerable amount of retained austenite for TRIP 780 steel. The ultimate tensile strength can reach about 1200 MPa with elongation above 16% for TRIP 780, that is much higher than the one solely treated by Q&P process. Tensile tests showed that both steels with the novel combined process achieved a good combination of strength and ductility, indicating that the new process is promising for the new generation of advanced high strength steels.
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Chen, M., Wu, R., Liu, H. et al. An ultrahigh strength steel produced through deformation-induced ferrite transformation and Q&P process. Sci. China Technol. Sci. 55, 1827–1832 (2012). https://doi.org/10.1007/s11431-012-4880-z
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DOI: https://doi.org/10.1007/s11431-012-4880-z