Synergistic preparation of forsterite-spinel refractory materials from ferronickel slag and ferrochromium slag

Abstract

The viability of synergistic preparing refractory material from ferronickel slag (FNS) and ferrochromium slag (FCS) has been confirmed based on the phase and microstructural transformation behavior of FNS and FCS during the sintering process in this research. The thermodynamic analysis results have shown that increasing magnesia additions at varying FCS/(FCS+FNS) ratios can result in the development of high-melting-point phases. The thermogravimetric-differential thermal analysis, thermal expansion tester, X-ray diffraction, and scanning electron microscope and energy-dispersive X-ray spectrometer analysis indicated that both the FCS/(FCS+FNS) ratio and magnesia addition have a significant impact on the transformation behavior of FNS and FCS during the sintering process. Specifically, as the FCS/(FCS+FNS) ratio increased, the temperature for generating the liquid phase decreased. By controlling the FCS/(FCS+FNS) ratio of 0.3 and magnesia addition of 30 wt.%, the expansion ratio of the FCS/(FCS+FNS) system during the sintering process was noticeably lower compared to that of the FCS and FNS demonstrating excellent densification.