Effect of Nb alloying on microstructure of high-Cr cast iron rolls
WANG Xi-zao1,2, ZHANG Bo-han1,2, LI Hao-nan2,3, LIU Jie-bing4, QIAO Gui-ying2,3, XIAO Fu-ren1,2
1. Key Lab of Metastable Materials Science and Technology and Hebei Key Lab for Optimizing Metal Product Technology and Performance, College of Materials Science and Engineering, Yanshan University, Qinhuangdao 066004, Hebei, China;
2. Hebei Key Lab for Optimizing Metal Product Technology and Performance, College of Materials Science and Engineering, Yanshan University, Qinhuangdao 066004, Hebei, China;
3. Key Lab of Applied Chemistry of Hebei Province, School of Environment and Chemical Engineering, Yanshan University, Qinhuangdao 066004, Hebei, China;
4. Hebei Technology Innovation Centre for Roller Green Manufacturing, Xingtai Delong Machinery and Mill Roll Co., Ltd., Xingtai 054009, Hebei, China
Microalloying is an important method to refine the solidification microstructure and improve the mechanical properties and service life of high-Cr cast iron rolls. The effect of Nb microalloying on the microstructure and hardness of high-Cr cast iron was studied. Meanwhile, the refining mechanism of Nb on the solidification microstructure of high-Cr cast iron was analyzed by Thermo-Calc software. The results show that Nb microalloying can significantly refine the solidification microstructure and improve the hardness of high-Cr cast iron rolls. The improving of Nb microalloying on microstructure of high-Cr cast iron depends on the precipitation temperature of MC type carbide and its promotion of nucleation for austenite and eutectic M7C3carbides. As Nb mass fration is 0.5%, the hardness of high-Cr cast iron rolls is the highest. Further increase of Nb content can significantly refine the microstructure of high-Cr cast iron rolls, but reduce the hardness.
王锡灶, 张博涵, 李浩楠, 刘杰兵, 乔桂英, 肖福仁. Nb合金化对高Cr铸铁轧辊组织的影响[J]. 中国冶金, 2022, 32(2): 60-66.
WANG Xi-zao, ZHANG Bo-han, LI Hao-nan, LIU Jie-bing, QIAO Gui-ying, XIAO Fu-ren. Effect of Nb alloying on microstructure of high-Cr cast iron rolls[J]. China Metallurgy, 2022, 32(2): 60-66.
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2022, Vol. 32 
