Effect of Final Rapid Cooling Temperature on Ultra-Fine Carbides of Ti-Mo Ferrite Matrix Microalloyed Steel

Abstract:

The size and distribution of nanoscale precipitate particles in Ti-Mo ferrite matrix microalloyed steel under three different final rapid cooling temperatures were studied by scanning electron microscopy(SEM), transmission electron microscope(TEM) and microhardness test. The results show that the interphase precipitation could be weakened by the excessive final rapid cooling temperature. A higher supersaturated solid solubility and high-density dislocation in ferrite matrix can be obtained under a relatively lower final rapid cooling temperature, which makes it easier to precipitate in ferrite. The related thermodynamic analysis indicated that the precipitation behavior was influenced by the final rapid cooling temperature during austenite/ferrite region. It is not conducive to get a large amount of small size precipitates in Ti-Mo ferrite matrix microalloyed steel when the final rapid cooling temperature is too high or low.

• Periodical: Materials Science Forum (Volume 926)
• Pages: 3-10
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.926.3
• Online since: July 2018
• Authors: Zhi Chen Yu, Zhen Li Mi*, Qing Wu Cai, Jin Guo, Na Gong
• Keywords: Final Rapid Cooling Temperature, Thermodynamic Model, Ti-Mo Microalloyed Steel, Ultra-Fine Carbides

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