Growth Characteristics and Kinetics of Niobium Carbide Coating Obtained on AISI 52100 by Thermal-reactive Diffusion Technique
来源期刊:Journal Of Wuhan University Of Technology Materials Science Edition2014年第4期
论文作者:严绍进 王洪福 SUN Qikun HE Peng PANG Chengang WANG Huachang WANG Ailing
文章页码:808 - 812
摘 要:Niobium carbide coating was produced by thermal-reactive diffusion technique on AISI 52100 steel in salt bath at 1 123 K, 1 173 K, and 1 223 K for 1, 2, 4, and 6 hours. The salt consisted of borax, sodium fl uoride, boron carbide, and niobium pentoxide. The presence of NbC phase on the steel surface was confi rmed by X-ray diffraction analysis. Microscopic observation showed that niobium carbide coating formed on the substrate was smooth and compact. There was a distinct and fl at interface between the coating and substrate. The micro-hardness of niobium carbide coating was 2892±145HV. The thickness of coating ranged from 1.6 μm to 14μm. The forming kinetics of niobium carbide coating was revealed. Moreover, a contour diagram derived from experimental data was graphed for correct selection of process parameters. Some mathematical equations were built for predicting the coating thickness with predetermined processing temperature and time. The results showed that these mathematical equations are very practical as well as the kinetics equation.
严绍进1,王洪福1,2,SUN Qikun2,HE Peng2,PANG Chengang3,WANG Huachang2,WANG Ailing1
1. School of Mechanical and Power Engineering, North University of China2. School of Materials Science and Engineering, Wuhan University of Technology3. Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology
摘 要:Niobium carbide coating was produced by thermal-reactive diffusion technique on AISI 52100 steel in salt bath at 1 123 K, 1 173 K, and 1 223 K for 1, 2, 4, and 6 hours. The salt consisted of borax, sodium fl uoride, boron carbide, and niobium pentoxide. The presence of NbC phase on the steel surface was confi rmed by X-ray diffraction analysis. Microscopic observation showed that niobium carbide coating formed on the substrate was smooth and compact. There was a distinct and fl at interface between the coating and substrate. The micro-hardness of niobium carbide coating was 2892±145HV. The thickness of coating ranged from 1.6 μm to 14μm. The forming kinetics of niobium carbide coating was revealed. Moreover, a contour diagram derived from experimental data was graphed for correct selection of process parameters. Some mathematical equations were built for predicting the coating thickness with predetermined processing temperature and time. The results showed that these mathematical equations are very practical as well as the kinetics equation.
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