Measuring and Modeling Viscosity of CaO-Al2O3-SiO2(-K2O) Melt
نویسنده
چکیده
The effect of K2O on viscosity in CaO-SiO2-Al2O3 melt has been measured by a rotating spindle viscometer. It is indicated from the experimental results that viscosity first increases then decreases with the increasing content of K2O; the maximum viscosity occurs in the field of K2O/ Al2O3 > 1. After gradually adding K2O, the transformation of bridging oxygen (from being bonded with Al ion charge compensated by Ca ion to that compensated by K ion, for the higher priority of K ion relative to Ca ion) increases the viscosity, whereas the increase of content of nonbridging oxygen decreases viscosity. The two factors lead to the complicate variation behavior of viscosity. The viscosity model proposed in our previous papers describes this phenomenon well.
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