Abstract
Thermal analysis plays a key role in the online inspection of molten iron quality. Different solidification process of molten iron can be reflected by thermal analysis curves, and silicon is one of important elements affecting the solidification of molten iron. In this study, FeSi75 was added in one chamber of the dual-chamber sample cup, and the influences of FeSi75 additive on the characteristic values of thermal analysis curves and vermiculating rate were investigated. The results show that with the increase of FeSi75, the start temperature of austenite formation TAL firstly decreases and then increases, but the start temperature of eutectic growth TSEF, the lowest eutectic temperature TEU, temperature at maximum eutectic reaction rate TEM, and highest eutectic temperature TER keep always an increase. The temperature at final solidification point TES has little change. The FeSi75 additive has different influences on the vermiculating rate of molten iron with different vermiculation, and the vermiculating rate increases for lower vermiculation molten iron while decreases for higher one. According to the thermal analysis curves obtained by a dual-chamber sample cup with 0.30wt.% FeSi75 additive in one chamber, the vermiculating rate of molten iron can be evaluated by comparing the characteristic values of these curves. The time difference ΔtER corresponding to the highest eutectic temperature TER has a closer relationship with the vermiculating rate, and a parabolic regression curve between the time difference ΔtER and vermiculating rate η has been obtained within the range of 65% to 95%, which is suitable for the qualified melt.
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References
Shi D, Kang K, Gao G, et al. System and experiment on fast testing vermicular graphite percent in cast iron based on ultrasonic longitudinal wave. Materials Transactions, 2016, 57(4): 544–548.
Hernando J C, Domeij B, Gonzalez D, et al. New experimental technique for nodularity and Mg fading control in compacted graphite iron production on laboratory scale. Metallurgical and Materials Transactions A, 2017, 48(11): 5432–5441.
Ribeiro C A S, Santos D, Baumgart W, et al. New approach to the use of thermal analysis to predict microstructure and mechanical properties of as-cast ductile iron. International Journal of Cast Metals Research, 2003, 16(1–3): 47–52.
Stefanescu D M. Thermal analysis-theory and applications in metalcasting. International Journal of Metalcasting, 2015, 9(1): 7–22.
Shi G Q, Yang Z, Li J P, et al. Investigation on the graphite nucleation and growth mechanism of the compacted graphite iron. Journal of Materials Research and Technology, 2020, 9(4): 8186–8196.
Kanno T, Iwami Y, Kang I. Prediction of graphite nodule count and shrinkage tendency in ductile cast iron, with 1 cup thermal analysis. International Journal of Metalcasting, 2017, 11(1): 94–100.
Hernando J C, Elfsberg J, Ghassemali E, et al. The effect of coarsening of primary austenite on the ultimate tensile strength of hypoeutectic compacted graphite Fe-C-Si alloys. Scripta Materialia, 2019, 168: 33–37.
Wang L, Nakae H. Influence of factors on thermal analysis parameter θ predicting shrinkage tendency. Journal of Japan Foundry Engineering Society, 2019, 91(4): 213–220.
Kanno T, Iwami Y, Kang I. Prediction of graphite nodule count and shrinkage tendency of spheroidal graphite cast iron by one cup thermal analysis. Materials Transactions, 2018, 59(3): 456–461.
Shi D Q, Tang H Y, Li C, et al. The feasibility of acquiring a thermal analysis cooling curve by wet sample cup made of green sand. JOM, 2011, 63(5): 35–38.
Cree J, Grybush I, Robles M, et al. Statistical comparisons of four (4) different thermal analysis sample cup types for chemistry control of ductile base iron. International Journal of Metalcasting, 2021, 15(3): 729–746.
Liu J H, Yan J S, Zhao X B, et al. Precipitation and evolution of nodular graphite during solidification process of ductile iron. China Foundry, 2020, 17(4): 260–271.
Zakharchenko E, Sirenko E, Goncharov A, et al. New computer method of derivative thermal express analysis of cast iron for operational prediction of quality of melts and castings. Journal of Casting and Materials Engineering, 2019, 3(2): 31–42.
Jiang A, Tian X, Song H, et al. Evaluation of vermicularity of compacted graphite iron based on multiple characteristic points of thermal analysis. Materials Transactions, 2021, 62(5): 675–679.
Kanno T, You Y, Kang I, et al. Prediction of chilling tendency in cast iron using three cups thermal analysis system. Journal of Japan Foundry Engineering Society, 1998, 70(11): 773–778.
Regordosa A, Torre U, Loizaga A, et al. Microstructure changes during solidification of cast irons: Effect of chemical composition and inoculation on competitive spheroidal and compacted graphite growth. International Journal of Metalcasting, 2020, 14(3): 681–688.
Takeda H, Yoneda H, Asano K. Effect of silicon and bismuth on solidification structure of thin wall spheroidal graphite cast iron. Materials Transactions, 2009, 51(1): 176–185.
Lekakh S N. Engineering nucleation kinetics of graphite nodules in inoculated cast iron for reducing porosity. Metallurgical and Materials Transactions B, 2019, 50(4): 890–902.
Firican M C, Riposan I. Graphite phase characteristics in compacted/vermicular graphite cast iron inoculated in the mould. Advanced Materials Research, 2015, 1128: 72–79.
Bhat M N, Khan D M A, Singh K K. Speed of recalescence as a measure of graphite nucleation in spheroidal graphite cast iron castings. International Journal of Metalcasting, 2021, 15(2): 602–612.
Bhat M N, Khan D M, Singh K K. Thermal analysis and graphitization ability of spheroidal graphite cast iron preconditioned by Al, Zr, Ca-FeSi. International Journal of Metalcasting, 2019, 13(4): 928–936.
Stan S, Chisamera M, Riposan I, et al. Application of thermal analysis to monitor the quality of hypoeutectic cast irons during solidification in sand and metal moulds. Journal of Thermal Analysis and Calorimetry, 2011, 110(3): 1185–1192.
Riposan I, Stan S, Chisamera M, et al. Simultaneous thermal and contraction/expansion curves analysis for solidification control of cast irons. China Foundry, 2020, 17(2): 96–110.
Cojocaru A M, Riposan I, Stan S. Solidification influence in the control of inoculation effects in ductile cast irons by thermal analysis. Journal of Thermal Analysis and Calorimetry, 2019, 138(1): 2131–2143.
Stefanescu D M, Suarez R, Kim S B. 90 years of thermal analysis as a control tool in the melting of cast iron. China Foundry, 2020, 17(2): 69–84.
Kanno T, Iwami Y, Kang I. Influence of various elements on primary crystal temperature and carbon equivalent in hypoeutectic cast iron. Materials Transactions, 2019, 60(9): 1983–1988.
Stefanescu D M, Alonso G, Larranaga P, et al. On the crystallization of graphite from liquid iron-carbon-silicon melts. Acta Materialia, 2016, 107: 102–126.
Vicente A D A, Sartori Moreno J R, Santos T F D A, et al. Nucleation and growth of graphite particles in ductile cast iron. Journal of Alloys and Compounds, 2019, 775: 1230–1234.
Fredriksson H. Inoculation of iron-base alloys. Materials Science and Engineering, 1984, 65(1): 137–144.
Alonso G, Stefanescu D M, Larranaga P, et al. Graphite nucleation in compacted graphite cast iron. International Journal of Metalcasting, 2020, 14(4): 1162–1171.
Fesenko M, Fesenko A. In-mould graphitizing, spheroidizing, and carbide stabilizing inoculation of cast iron melt. Progress in Physics of Metals, 2020, 21(1): 83–101.
Koriyama S, Kanno T, Iwami Y, et al. Investigation of the difference between carbon equivalent from carbon saturation degree and that from liquidus. International Journal of Metalcasting, 2020, 14(3): 774–781.
Dioszegi A, Svensson I L. On the problems of thermal analysis of solidification. Materials Science and Engineering: A, 2005, 413–414: 474–479.
Ai S, Xu Z, Liu Z, et al. Evolution of inoculation thermal analysis and solidification morphology of compacted graphite iron. Kovove Materialy, 2021, 59(1): 51–57.
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The authors gratefully acknowledge the financial support of the State Key Laboratory of Engine Reliability (skler-202105).
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The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
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De-quan Shi Male, born in 1977, Ph.D, Professor. His research interests mainly focus on rapid casting technology, fast measurement and control technology in foundry.
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Shi, Dq., Liu, Zy., Gao, Gl. et al. Effect of FeSi additive in dual-chamber sample cup on thermal analysis characteristic values and vermiculating rate of compacted graphite iron. China Foundry 21, 91–100 (2024). https://doi.org/10.1007/s41230-024-2142-x
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DOI: https://doi.org/10.1007/s41230-024-2142-x