Mechanical Properties and Precipitation Behavior of Ti-Mo Microalloyed Medium-Carbon Steel during Ultrafast Cooling Process

Abstract:

We describe here the mechanical property evolution and precipitation hardening behavior under different cooling conditions including ultrafast cooling (UFC) + air cooling process and accelerated cooling (ACC) + air cooling process in a Ti-Mo microalloyed medium carbon steel is described here. The results demonstrate that the cooling procedure after hot rolling has a significant influence on the mechanical properties of the microalloyed steel. The yield strength and tensile strength that were obtained by ultrafast cooling (UFC) + air cooling process were higher than those from accelerated cooling (ACC) + air cooling process, while the elongation was slightly reduced. Microstructural characterization indicated that grain refinement and precipitation hardening were the primary reasons for the increase in strength of the experimental steel. Ultrafast cooling increased the density of dislocations and refined the grain size. Average size of precipitates containing Ti and Mo was 3~6 nm in ultrafast cooling (UFC) + air cooling process, while average precipitate size obtained by accelerated cooling (ACC) + air cooling process was 6~9 nm. Keywords: Ti-Mo medium-carbon steel; Precipitation; Ultra fast cooling process; accelerated cooling process

• Periodical: Advanced Materials Research (Volume 922)
• Pages: 86-93
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.922.86
• Online since: May 2014
• Authors: Xiang Tao Deng, Zhao Dong Wang*, R.D.K. Misra, Jie Han, Guo Dong Wang
• Keywords: Accelerated Cooling Process, Precipitation, Ti-Mo Medium-Carbon Steel, Ultra Fast Cooling Process

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