J Mater Sci Technol ›› 2011, Vol. 27 ›› Issue (2): 127-130.

• Novel Processing and Characterization Methods • Previous Articles     Next Articles

Hybrid Friction Stir Welding of High-carbon Steel

Don-Hyun Choi1), Chang-Yong Lee2), Byung-Wook Ahn1), Jung-Hyun Choi1), Yun-Mo Yeon3), Keun Song3), Seung-Gab Hong4), Won-Bae Lee4), Ki-Bong Kang4), Seung-Boo Jung1)     

  1. 1) School of Advanced Materials Science and Engineering, Sungkyunkwan University, 300 Cheoncheon-dong, Jangan-gu, Suwon, Gyeonggi-do 440-746, South Korea
    2) Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, 335 Gwahangno, Yuseong-gu, Daejeon 305-701, South Korea
    3) Department of Advanced Materials Application, Suwon Science College 9-10, Botong-li, Jeongnam-myeon, Hwasung, Gyeonggi-do 445-742, South Korea
    4) Technical Research Lab, POSCO Corp., Goedong-dong, Nam-gu, Pohang, Gyeongbuk, 790-785, South Korea
  • Received:2009-04-14 Revised:2010-12-18 Online:2011-02-28 Published:2011-02-28
  • Contact: Seung-Boo Jung

Abstract: A high-carbon steel joint, SK5 (0.84 wt% C), was successfully welded by friction stir welding (FSW), both without and with a gas torch, in order to control the cooling rate during welding. After welding, the weld zone comprised gray and black regions, corresponding to microstructural variation: a martensite structure and a duplex structure of ferrite and cementite, respectively. The volume fraction of the martensite structure and the Vickers hardness in the welds were decreased with the using of the gas torch, which was related with the lower cooling rate.

Key words: Friction stir welding, High-carbon steel, Transformation, Martensite