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Crystallization behavior of F-free mold fluxes

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Abstract

The time-temperature-transformation (TTT) diagrams of F-free mold fluxes was constructed using single hot thermocouple technique (SHTT) and confocal scanning laser microscopy (CSLM) to study the crystallization behavior of F-free mold fluxes. The tendency of crystallization is found to increase whereas the incubation time decreases with increasing basicity. Zirconia addition enhances the crystallization tendency due to its limited solubility in the slag melt and the solid particles acting as nucleation sites. Pseudo-wollastonite is found to precipitate in the slag with low basicity (CS-1 and CS-2), kilchoanite and larnite are formed with further increasing basicity (CS-3), and larnite is finally formed as the basicity beyond unit (CS-4). The crystal morphology changes with varying compositions and isothermal temperatures. The measured growth rate is found to be linear with time under isothermal conditions and decreases with increasing isothermal temperature.

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Authors and Affiliations

  1. College of Engineering, Peking University, Beijing, 100871, China

    Zuo-tai Zhang & Ying-yi Zhang

  2. College of Materials Science and Engineering, Chongqing University, Chongqing, 400044, China

    Guang-hua Wen

Authors
  1. Zuo-tai Zhang
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  2. Guang-hua Wen
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  3. Ying-yi Zhang
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Correspondence to Zuo-tai Zhang.

Additional information

This work was financially supported by the National Natural Science Foundation of China (No.50902003) and the Major State Basic Research Development Program of China (No.2007CB613608)

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Zhang, Zt., Wen, Gh. & Zhang, Yy. Crystallization behavior of F-free mold fluxes. Int J Miner Metall Mater 18, 150–158 (2011). https://doi.org/10.1007/s12613-011-0415-z

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  • DOI: https://doi.org/10.1007/s12613-011-0415-z

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