著者
Toshihiro Tsuchiyama Kurato Inoue Katsutoshi Hyodo Daichi Akama Nobuo Nakada Setsuo Takaki Tamotsu Koyano
出版者
The Iron and Steel Institute of Japan
雑誌
ISIJ International (ISSN:09151559)
巻号頁・発行日
vol.59, no.1, pp.161-168, 2019-01-15 (Released:2019-01-17)
参考文献数
37
被引用文献数
9 16

The microstructure and hardness of martensite in Fe–C and Fe–N alloys with up to 7.5 at% contents of carbon and nitrogen, respectively, were compared. Their difference in hardness was discussed based on four strengthening mechanisms. The martensitic structures of Fe–C and Fe–N alloys with equal contents of carbon and nitrogen, respectively, were nearly identical, except for the amount of retained austenite. Furthermore, Fe–C alloy was considerably harder than Fe–N alloy. This discrepancy gradually increased with carbon and nitrogen contents. The enhanced hardness of Fe–C alloy martensite was attributed to its higher dislocation density and the stronger pinning force of interstitial carbon atoms on dislocations.