A Study on the Microstructure of Ultra Low Carbon Bainitic Steels by RPC Technique

Abstract:

The effect of tempering process on the microstructure of ultra low carbon bainitic (ULCB) steel produced by relaxation precipitation controlled phase transformation (RPC) has been investigated by transmission electron microscopy (TEM) and electron backscattered diffraction (EBSD). The results showed that the final microstructure mainly contained lath-like bainitic ferrite, granular bainite and martensite-austenite (MA) constituent in ULCB steels. On tempering at 650°C a slight increase was detected in the effective grain size as the strain-induced precipitates pinned up the dislocation walls and subgrains. After tempering at 700°C, bainitic ferrite laths started to coarsen and polygonal ferrite occurred. The effective grain size of ULCB steels in as-rolled condition was 1.5 μm at the tolerance of 10o~15o measured by EBSD technique.

• Periodical: Materials Science Forum (Volumes 561-565)
• Pages: 2107-2110
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.561-565.2107
• Online since: October 2007
• Authors: Zhi Fen Wang, Shao Kang Pu, Y. Guan, Ping He Li, Li Xin Wu, Qing Feng Chen
• Keywords: Precipitation, Tempering, Ultra Low Carbon Bainitic Steel

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