In this study, thermodynamics software was employed to calculate the ternary phase diagram of CaO-Al2O3-SiO2 and the quaternary phase diagram of CaO-Al2O3-B2O3-SiO2 first. Then, the specific contents of the main components of B2O3 and CaO-Al2O3-SiO2 slag system were determined according to the principle of low melting point selection. The melting and crystallization properties of B2O3 mold flux with various contents were studied experimentally by means of Brookfield rotational viscometer and DHTT-II melting crystallization temperature tester. Furthermore, the simulation of the molten slag was conducted by the molecular dynamics software. The microstructure of the mold flux was analyzed and an in-depth discussion of the relationship between the properties and the structure of the mold flux was carried out. It could be found from the results that B2O3 exerted an exceptional effect on the viscosity and transition temperature of CaO-Al2O3-SiO2 system. When the content of B2O3 was no higher than 9%, the increase of B2O3 content would result in sharp reduction in viscosity and transition temperature of the slag. Additio-nally, the growing B2O3 content in the mold flux also leaded to prolonging of the crystallization time and complete crystallization time of the mold flux. The B-O coordination structure is the most stable compared to the Al-O and Si-O coordination structures. In this system, B ions can replace Si and Al ions to form a B-O tricoordinate structure and a B-O tetracoordinate structure. Meanwhile, the structure altered from a compact framework structure to a relaxed layer structure, accompanied by a lowered slag polymerization degree and a declined viscosity. © 2019, Materials Review Magazine. All right reserved.
