Effect of Al2O3/(B2O3 + Na2O) Ratio on CaO-Al2O3-Based Mold Fluxes: Melting Property, Viscosity, Heat Transfer, and Structure
Abstract
CaO-Al2O3-based mold fluxes, which are under development for the continuous casting of high-Al steel, contain fluxing compounds, such as Na2O and B2O3. The reaction between [Al] and the fluxing agents in mold fluxes leads to an increase in Al2O3 and a decrease in B2O3 and Na2O concentrations, changing the properties of mold fluxes. The effect of the Al2O3/(B2O3 + Na2O) ratio on the melting properties, viscosity, heat transfer, and structure of the CaO-Al2O3-based mold fluxes is presented in this work. The increase of the Al2O3/(B2O3 + Na2O) ratio in the fluxes raised the melting temperature and high-temperature viscosity of mold fluxes but decreased the heat transfer rate across the flux disks. It also enhanced the degree of polymerization by promoting the formation of 3-D aluminate structure, which accounted for the change of the viscous behavior.
- Publication:
-
Metallurgical and Materials Transactions B
- Pub Date:
- December 2019
- DOI:
- 10.1007/s11663-019-01711-z
- Bibcode:
- 2019MMTB...50.2794Y