Characterization of age hardening mechanism of low-temperature aged low-carbon steel by transmission electron microscopy
Characterization of age hardening mechanism of low-temperature aged low-carbon steel by transmission electron microscopy
复制标题
透射电镜表征低温时效低碳钢时效硬化机理
DOI：
10.1016/j.matchar.2021.111579
复制
发表时间：
2022
影响因子：
4.7
通讯作者：
Kenji Kaneko
中科院分区：
文献类型：
--
作者：
Yasuhito Kawahara;Takuya Maeda;Keisuke Kinoshita;Jun Takahashi;Hideaki Sawada;Ryo Teranishi;Kenji Kaneko
323 K低温时效处理导致低碳铁素体钢从983 K淬火后硬度急剧增加，这可能是由碳团簇和/或细小的ε-碳化物引起的。在这项研究中，透射电子显微镜（TEM）分析进行了表征在低温时效处理过程中的微观结构的变化。在峰值硬度出现之前，碳团簇呈锯齿状均匀分布。在峰值硬度的后期，ε-碳化物在碳团簇中部分析出，表明碳团簇可能是ε-碳化物的前驱体。原位拉伸TEM观察表明，位错运动为自由滑移型，碳团簇和细小碳化物与位错以切割型相互作用。计算了位错间的相互作用力，表明晶格失配是位错间相互作用的重要机制。
Low-temperature aging treatment at 323 K results in the dramatical increase in hardness in low-carbon ferritic steels quenched from 983 K, possibly caused by carbon clusters and/or fine ε-carbides. In this study, transmission electron microscopy (TEM) analysis was carried out to characterize the change of the microstructure during the low-temperature aging treatment. Until the early stage of the peak hardness, the carbon clusters were formed homogeneously with zig-zag structures. At the latter stage of the peak hardness, it was found that the ε-carbides were partially precipitated within the carbon clusters, which suggested that the carbon clusters might have acted as the precursors of ε-carbides. In-situ tensile TEM observations showed that dislocation motions were free-glide type, and carbon clusters and fine-carbides interacted with dislocations via cutting-type. Dislocation interaction force was also evaluated, which suggested that the lattice misfit played as important role of the interaction mechanism.