Micro-Structure Refinement in Low Carbon High Manganese Steels Through Ti-Deoxidation,Characterization and Effect of Secondary Deoxidation Particle(s)
This paper investigates the effect of de-oxidation inclusions on micro-structure in low carbon (0.07 mass%),high Mn (0.9 mass%) steel.De-oxidation tests were carried out by adding either aluminum (0.05 mass%) or titanium (0.05,0.03 or 0.015 mass%) to an iron melt in a 400 g-scale vacuum furnace.A Confocal Scanning Laser Microscope (CSLM) was used to evaluate the effect of cooling rate by re-melting and quenching during solidification.Fine secondary de-oxidation particles were obtained in the Ti-killed samples,and the particle density increased with increasing oxygen content,and their size decreased with increasing the cooling rate during solidification.The secondary Ti de-oxidation particles were found to have an effect on microstructure evolution,such as solidifying microstructure,austenite grain growth and austenite decomposition.The de-oxidation particles were examined through FE-TEM and were identified to be TiO,MnTiO3 and Mn2TiO4,in low oxygen (O=7ppm) and high oxygen (O=56,81ppm) Ti-killed steels respectively.The effect of the particles on ferrite formation was evaluated through thermo-mechanical treatments.TiO was the most effective for promoting ferrite formation through heterogeneous nucleation.The particles contributed to ferrite formation in the following order,TiO>TiN>MnS>MnTiO3>Ti2O3.
Low-carbon steel De-oxidation Aluminum Titanium Inclusion Solidification microstructure Confocal-laser-scanning-microscopy Ferrite formation,Grain growth,Ti-oxide
Naoki Kikuchi Seiji Nabeshima Takako Yamashita Yasuo Kishimoto Seetharaman Sridhar Tetsuya Nagasaka
Steel Research Lab,JFE Steel Corporation Department of Material Science & Engineering,Carnegie Mellon University National Energy Technology Laboratory;Graduate School of Environmental Studies,Tohoku University
国际会议
Asia Steel International conference 2012(第五届亚洲钢铁大会)
北京
英文
1-6
2012-09-23（万方平台首次上网日期，不代表论文的发表时间）