Experimental crystallization of synthetic V-bearing steelmaking slag with Al₂O₃ doped

Abstract

The phenomenon of crystallization was implemented in the synthetic V-bearing steelwork slag based on the composition of factory slag from the Masteel Co., and the possibility of undercooling as a technique to precipitate V-concentration phase was demonstrated. The effect of 20 wt% Al₂O₃ additive introduced into the slag on intensifing the precipitation was also investigated. X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX) were used to investigate the slag after heat treatment. It is demonstrated that gehlenite and grossite are the major crystalline phases. Whitlockite with a high content of V₂O₅ (called V-concentration phase hereafter) nucleates homogenously and hetergenously and grows with decreasing undercooling. At 1548 K, the crystals of V-concentration phase grow up as the duration of time, with a medium grain size of 25 μm at 300 min holding time.

Keywords

V-bearing steelwork slag / undercooling / V-concentration phase / nucleation / grain growth

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