Qi-hang Han, Yong-lin Kang, Xian-meng Zhao, Lu-feng Gao, and Xue-song Qiu, High-temperature properties and microstructure of Mo microalloyed ultra-high-strength steel, Int. J. Miner. Metall. Mater., 18(2011), No. 4, pp. 407-412. https://doi.org/10.1007/s12613-011-0454-5
Cite this article as:
Qi-hang Han, Yong-lin Kang, Xian-meng Zhao, Lu-feng Gao, and Xue-song Qiu, High-temperature properties and microstructure of Mo microalloyed ultra-high-strength steel, Int. J. Miner. Metall. Mater., 18(2011), No. 4, pp. 407-412. https://doi.org/10.1007/s12613-011-0454-5
Qi-hang Han, Yong-lin Kang, Xian-meng Zhao, Lu-feng Gao, and Xue-song Qiu, High-temperature properties and microstructure of Mo microalloyed ultra-high-strength steel, Int. J. Miner. Metall. Mater., 18(2011), No. 4, pp. 407-412. https://doi.org/10.1007/s12613-011-0454-5
Citation:
Qi-hang Han, Yong-lin Kang, Xian-meng Zhao, Lu-feng Gao, and Xue-song Qiu, High-temperature properties and microstructure of Mo microalloyed ultra-high-strength steel, Int. J. Miner. Metall. Mater., 18(2011), No. 4, pp. 407-412. https://doi.org/10.1007/s12613-011-0454-5
The high-temperature mechanical properties and microstructure of forging billets of C-Si-Mn-Cr and C-Si-Mn-Cr-Mo ultra-high-strength cold-rolled steels (tensile strength≥1000 MPa, elongation≥10%) were studied. Through the comparison of reduction in area and hot deformation resistance at 600–1300℃, the Mo-containing steel was found to possess a higher strength and a better plasticity than the Mo-free one. The equilibrium phase diagram and atom fraction of Mo in different phases at different temperatures were calculated by Thermo-Calc software (TCW). The results analyzed by using transmission electron microscopy and TCW show that precipitates in the Mo-containing steel are primarily M23C6, which promote pearlite formation. The experimental data also show that a lower ductility point existing in the Mo-free steel at 850℃ is eliminated in the Mo-containing one. This is mainly due to the segregation of Mo at grain boundaries investigated by electron probe microanalysis (EPMA), which improves the strength of grain boundaries.
The high-temperature mechanical properties and microstructure of forging billets of C-Si-Mn-Cr and C-Si-Mn-Cr-Mo ultra-high-strength cold-rolled steels (tensile strength≥1000 MPa, elongation≥10%) were studied. Through the comparison of reduction in area and hot deformation resistance at 600–1300℃, the Mo-containing steel was found to possess a higher strength and a better plasticity than the Mo-free one. The equilibrium phase diagram and atom fraction of Mo in different phases at different temperatures were calculated by Thermo-Calc software (TCW). The results analyzed by using transmission electron microscopy and TCW show that precipitates in the Mo-containing steel are primarily M23C6, which promote pearlite formation. The experimental data also show that a lower ductility point existing in the Mo-free steel at 850℃ is eliminated in the Mo-containing one. This is mainly due to the segregation of Mo at grain boundaries investigated by electron probe microanalysis (EPMA), which improves the strength of grain boundaries.