Influence of B2O3 on Reactive and Non-Reactive Wetting Behavior of CaO-SiO2-MgO-Al2O3-B2O3 System

Boron oxide is introduced into slag as a flux, significantly lowering the liquidus temperature; however, this advantage is accompanied by several undesirable consequences. This study aims to evaluate the impact of boron oxide addition on the wetting reactivity of the CaO-SiO2-MgO-Al2O3-B2O3 slag system, particularly on platinum and graphite substrates, which are commonly utilized for wettability investigations of such systems. The slag system was modified to incorporate varying concentrations of B2O3, reaching up to 30 wt%, with the addition of this oxide at the expense of CaO and SiO2 in a constant ratio, while the contents of Al2O3 and MgO remained unchanged. High-temperature wettability tests were conducted at temperatures up to 1550 °C under a flow of high-purity argon atmosphere (99.9999%). For the platinum substrate, the results indicated non-reactive wetting, characterized by a decrease in wetting angles with increasing temperature and boron oxide content. Conversely, for the graphite substrate, the nature of wetting varied, resulting in either reactive or non-reactive behavior depending on the B2O3 content. Following the high-temperature experiments, additional analyses were performed using scanning electron microscopy (SEM) and energy-dispersive spectrometry (EDS). Furthermore, the powdered oxide systems underwent characterization through Fourier transform infrared spectroscopy (FTIR) and X-ray powder diffraction (XRPD).