Experimental Crystallization of Synthetic V-bearing Steelmaking Slag with Al2O3 Doped

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 20wt% 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 homogeneously and hetergeneously 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.