Effect of Mo and Ce on the second phase, microstructure and hardness of bainitic steel
ZHENG Li-li1,2, PENG Jun1,2, AN Sheng-li1,2, ZHANG Fang1,2, PENG Ji-hua1,2, WANG Xiao-xia3
1. College of Material and Metallurgy,Inner Mongolia University of Science and Technology, Baotou 014010, Nei Mongol, China; 2. Inner Mongolia Autonomous Region Key Laboratory of Advanced Ceramic Materials and Devices, Baotou 014010, Nei Mongol, China; 3. First Branch,Inner Mongolia First Machinery Group Co., Ltd., Baotou 014010, Nei Mongol, China
Abstract：In order to clarify the role of Mo,Ce,and Ti in bainitic steel,thermodynamic calculations and experiments were used to study the influence mechanism of Mo and Ce in titanium-containing bainite steel on the second phase precipitation,microstructure transformation and properties. The results showed that after adding Mo to the bainitic steel,part of it was dissolved in the steel matrix and the left part was precipitated in the form of molybdenum carbide. Titanium was mainly precipitated as C2S2Ti4. Cerium existed in the form of Ce2O3 and Ce2O2S in the bainite steel. After adding Ce,the second phase precipitation of titanium was mainly TiC. The addition of Mo increased the precipitation of Ti(C,N) by 13.12% and the average particle size was decreases by 0.043 μm. The addition of Ce increased the precipitation of Ti(C,N) by 28.97% and the particle size was decreased by 0.104 μm; Mo and Ce increased the retained austenite in the microstructure by 1.13% and 0.77%,respectively. However,the microstructure was granular bainite (GB) + lath martensite (M) + retained austenite (Aγ). After Mo and Ce were added,the hardness was increased by 54.5 HV and 27 HV,respectively.
郑丽丽, 彭军, 安胜利, 张芳, 彭继华, 王晓霞. Mo、Ce对贝氏体钢第二相及组织与硬度的影响[J]. 中国冶金, 2021, 31(7): 50-56.
ZHENG Li-li, PENG Jun, AN Sheng-li, ZHANG Fang, PENG Ji-hua, WANG Xiao-xia. Effect of Mo and Ce on the second phase, microstructure and hardness of bainitic steel[J]. China Metallurgy, 2021, 31(7): 50-56.
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2021, Vol. 31 
