TY - JOUR
T1 - Effect of Mo on precipitation behavior and tensile properties of Fe26Mn8Al1.2C–xMo lightweight austenitic steels
AU - Qiu, Xu Yang Fan
AU - Wang, Ying Chun
AU - Zeng, Kai Lun
AU - He, Jin
AU - Gao, Chong
AU - Xiong, Zhi Ping
AU - Cheng, Xing Wang
N1 - Publisher Copyright:
© China Iron and Steel Research Institute Group Co., Ltd. 2025.
PY - 2025
Y1 - 2025
N2 - The effect of Mo on dual-phase precipitation behavior and tensile properties of Fe26Mn8Al1.2C–(2–3.5 wt.%) Mo lightweight austenitic steels after annealing at 700 °C was investigated by electron backscatter diffraction, transmission electron microscopy, hardness and tensile tests. Alloying with Mo in the steels promotes the precipitation of Mo2C carbides while inhibits the precipitation of κ-carbides. The addition of Mo exceeding 2.5 wt.% facilitates the precipitation of intragranular Mo2C carbides, whereas with up to 2.5 wt.% Mo, only intergranular Mo2C carbides precipitate. With containing more Mo in the steels, the strength increases due to enhancement of precipitation strengthening and solid solution strengthening, while ductility gradually decreases. 3Mo steel exhibits excellent overall mechanical properties, with the synergistic increase in strength, ductility, and work-hardening rate, which can be attributed to the precipitation of fine intragranular Mo2C distributed uniformly in the matrix and the suppression of the formation of coarsened κ-carbides. However, in 3.5Mo steel, abundant coarsened Mo2C precipitation strongly interacts with dislocations to promote crack propagation along non-coherent interfaces, leading to a high initial work-hardening rate but severe ductility loss.
AB - The effect of Mo on dual-phase precipitation behavior and tensile properties of Fe26Mn8Al1.2C–(2–3.5 wt.%) Mo lightweight austenitic steels after annealing at 700 °C was investigated by electron backscatter diffraction, transmission electron microscopy, hardness and tensile tests. Alloying with Mo in the steels promotes the precipitation of Mo2C carbides while inhibits the precipitation of κ-carbides. The addition of Mo exceeding 2.5 wt.% facilitates the precipitation of intragranular Mo2C carbides, whereas with up to 2.5 wt.% Mo, only intergranular Mo2C carbides precipitate. With containing more Mo in the steels, the strength increases due to enhancement of precipitation strengthening and solid solution strengthening, while ductility gradually decreases. 3Mo steel exhibits excellent overall mechanical properties, with the synergistic increase in strength, ductility, and work-hardening rate, which can be attributed to the precipitation of fine intragranular Mo2C distributed uniformly in the matrix and the suppression of the formation of coarsened κ-carbides. However, in 3.5Mo steel, abundant coarsened Mo2C precipitation strongly interacts with dislocations to promote crack propagation along non-coherent interfaces, leading to a high initial work-hardening rate but severe ductility loss.
KW - Lightweight austenitic steel
KW - Mo addition
KW - Precipitation behavior
KW - Tensile property
KW - Work-hardening rate
UR - http://www.scopus.com/inward/record.url?scp=105006450063&partnerID=8YFLogxK
U2 - 10.1007/s42243-025-01488-3
DO - 10.1007/s42243-025-01488-3
M3 - Article
AN - SCOPUS:105006450063
SN - 1006-706X
JO - Journal of Iron and Steel Research International
JF - Journal of Iron and Steel Research International
M1 - 141683
ER -