Effect of Cr and C on microstructure evolution of medium carbon steels during friction stir welding process and their mechanical property

C. Cheng, K. Kadoi, S. Tokita, H. Fujii, K. Ushioda, H. Inoue

研究成果: Conference article査読

抄録

The aim of the present study was to investigate the effect of chromium and carbon in medium carbon steels on the microstructure evolution during FSW process and their mechanical property. The materials are dynamically recrystallized in austenite during FSW followed by phase transformation from austenite to ferrite, pearlite, bainite, and martensite. In the case of 0.2%C, the microstructure of the stir zone transited from pearlite and ferrite to bainite and martensite with the increase in chromium content. On the other hand, in the case of 0.4%C, the microstructure transited from pearlite to martensite with the increase in chromium content. The specimens of 0.2%C-4%Cr, 0.4%C-2%Cr and 0.4%C-4%Cr showed high tensile strength of over 1.5 GPa. In addition, even though the microstructures in the stir zones of the specimens are martensite, the elongation of 0.2%C-4%Cr was 31%while those of the others were less than 5%. TEM observation revealed that many tiny carbides precipitated in martensite of the stir zone of 0.2%C-4%Cr and micro twin formed in martensite in those of 0.4%C-2%Cr and 0.4%C-4%Cr. Thus, it was considered that auto-tempering occurred in the stir zone of 0.2%C-4%Cr during FSW process. The carbide precipitation in martensite is more effective to improve the tensile elongation compared with micro twin formation.

本文言語English
論文番号012032
ジャーナルJournal of Physics: Conference Series
1270
1
DOI
出版ステータスPublished - 2019 8 14
外部発表はい
イベント7th International Conference on Recrystallization and Grain Growth, ReX and GG 2019 - Ghent, Belgium
継続期間: 2019 8 42019 8 9

ASJC Scopus subject areas

  • 物理学および天文学(全般)

フィンガープリント

「Effect of Cr and C on microstructure evolution of medium carbon steels during friction stir welding process and their mechanical property」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

引用スタイル