。1018。 北京科技大学学报 2006年第11期 Mathematical simulation of steel flow and trajectory of inclusions in FTSC tundish ZHANG Caijun,ZHAO Tiecheng,AI Liqun Metallurgy and Energy Institute,Hebei Polytechnic University.Tangshan 063009 China ABSTRACT The three-dimensional flow field,temperature dist ribution,trajectory of inclusions,and re- moving rate of inclusions in a FTSC tundish were simulated by software FLUENT.The results show ed that the flow control devices of double effect pad and dam in the FTSC tundish had a significant influence on improving the flow field and temperature distribution and on increasing the removing rate of inclusions especially small inclusions (d<60um). KEY WORDS FTSC;tundish;fluid field;inclusion;moving trajectory;numerical simulation Comparison and analysis of dislocation density,morphology and evolution in mi- crostructure of low-carbon steel produced using different technologies YU Hao,KANG Yonglin,DONG Hongbo2 1)Materiak Science and Ergineering School University of Science and Technology Beijing.Beijing 100083 China 2)Jinan Iron Steel Group Co.,Jinan 250101.China ABSTRACT Three kinds of specimens were produced from hot strips of similar composition and same thickness(nominal gauge 4.0mm)but produced using different technologies,and the dislocation density of these strips was quantitatively measured by positron annihilation technique test.The dislocation morphology and evolution in microstructure of each pass for producing the 1.9mm hot strip using CSP (compact strip production )technology were observed under an H800 transmission electron microscope;its density was al- so quantitatively measured using the positron annihilation technique test,and the factors influencing the dis- location density during the production process were analyzed.The experimental results show that the dislo- cation density in the microstructure produced using CSP technology is higher than that in the microstructure produced using conventional technology.This result was discussed and confirmed on the basis of the finite element simulation and the theory relevant to dislocations. KEY WORDS compact strip production (CSP);microstructure;dislocation;positron annihilation tech- nique;finite element simulation Joumal of University of Science and Technology Beijing,2006,13(5):406] (C)1994-2019 China Academic Journal Electronic Publishing House.All rights reserved.http://www.cnki.netMathematical simulation of steel flow and trajectory of inclusions in FTSC tundish ZHANG Caijun , ZHAO Tiecheng , AI Liqun Metallurgy and Energy Institute , Hebei Polyt echnic University , Tangshan 063009 , C hina ABSTRACT The three-dimensional flow field , temperature distributio n , trajecto ry of inclusio ns, and re￾moving rate of inclusions in a FTSC tundish were simulated by software FLUENT .The results show ed that the flow control devices of double effect pad and dam in the FTSC tundish had a significant influence on improving the flow field and temperature distribution and on increasing the removing rate of inclusions especially small inclusions (d <60 μm). KEY WORDS FTSC ;tundish ;fluid field ;inclusion ;moving trajecto ry ;numerical simulation Comparison and analysis of dislocation density , morphology and evolution in mi￾crostructure of low-carbon steel produced using different technologies YU Hao 1), K ANG Yonglin 1), DONG Hongbo 2) 1)Materials Science and Engineering School, University of Science and Technology Beijing , Beijing 100083 , China 2)Jinan Iron &St eel Group Co ., Jinan 250101 , China ABSTRACT Three kinds of specimens were produced from hot strips of similar composition and same thickness (nominal gauge 4.0 mm)but produced using different technologies, and the dislocation density of these strips was quantitatively measured by positron annihilation technique test .The dislocation morphology and evolution in microstructure of each pass for producing the 1.9 mm hot strip using CSP (compact strip production)technology w ere observed under an H-800 transmission electron microscope ;its density w as al￾so quantitatively measured using the positron annihilation technique test , and the factorsinfluencing the dis￾location density during the production process w ere analyzed .The experimental results show that the dislo￾cation density in the microstructure produced using CSP technology is higher than that in the microstructure produced using co nventional technology .This result w as discussed and confirmed on the basis of the finite element simulation and the theory relevant to dislocations . KEY WORDS compact strip production (CSP);microstructure;dislocation ;positron annihilation tech￾nique ;finite element simulation [ 摘自 Journal of University of Science and Technology Beijing , 2006 , 13(5):406] · 1018 · 北 京 科 技 大 学 学 报 2006 年第 11 期