Formation of core-shell type structure in duplex martensitic steel
Formation of core-shell type structure in duplex martensitic steel
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双相马氏体钢核壳型结构的形成
DOI：
10.1016/j.scriptamat.2020.10.044
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发表时间：
2021
影响因子：
6
通讯作者：
H.Shirahata and R.Uemori
中科院分区：
文献类型：
--
作者：
K.Kaneko;T.Maeda;K.Ichino;Y.Kawahara;T.Masumura;T.Tsuchiyama;H.Shirahata and R.Uemori
为了更好地理解γ - α′和γ - α′马氏体相变，采用透射电镜研究了淬火态和临界间退火态中mn钢的显微组织。各相的取向关系分别为（1¯10）α′//(0001)ε、[111]α′//[11.2¯0]ε和（1¯10）α′//(1¯11)γ//(0001) ε、[111]α′//[110]γ//[11.2¯0]ε。此外，随着Mn浓度的梯度，核壳型微结构的存在得到了证实，α -马氏体被保留的γ包围。在临界间退火过程中，各相的Mn浓度依赖于Mn扩散控制的反向γ的生长。结果表明，临界间退火过程中Mn浓度的梯度影响了相的稳定性，导致ε/γ核壳结构的形成。
Microstructures of both as-quenched and intercritical-annealed medium-Mn steel were investigated by transmission electron microscopy to acquire a better understanding of γ–ɛ and γ–α′ martensitic transformations. The orientation relationships among each phases were determined as (1¯ 10) α′//(0001) ε,[111] α′//[11 2¯ 0] ε for the case of as-quenched sample, and (1¯ 10) α′//(1¯ 11) γ//(0001) ε,[111] α′//[110] γ//[11 2¯ 0] ε for the case of intercritical-annealed sample, respectively. In addition, the presences of core-shell type microstructures with the gradient of Mn concentration were confirmed with ɛ–martensite being surrounded by retained γ. Mn concentration of each phase was found dependent on the growth of reversed γ controlled by Mn diffusion during intercritical annealing. It was strongly suggested that the gradient of Mn concentration occurred during intercritical annealing affected the phase stability, which resulted in the formation of ε/γ core-shell microstructures.