Phase and microstructural evolution of BaZrO3‐CaZrO3 refractory and its interaction with titanium alloy melt

Abstract

AbstractIn this study, the effect of CaZrO3 additives on the phase and microstructure of BaZrO3 refractory were investigated as well as the interaction with titanium alloy melts. Results revealed that no second phase was observed in the BaZrO3 refractory with 10 and 20 mol% CaZrO3 additives, respectively, and the incorporation CaZrO3 additives promoted the densification and the growth of grains due to the generation of BaZrO3‐CaZrO3 solid solutions. Whereas, the appearance of CaZrO3 phase was in the BaZrO3 refractory with 30 mol% additive, indicating that the additive content excessed the solid solubility limit in the BaZrO3 refractory. Interaction analysis indicated that CaZrO3 additive could improve the performance of BaZrO3 refractory for resisting the penetration of Ti2Ni alloy melt. Meanwhile, an increasing extent of melt contamination by the BaZrO3 refractory was also detected with the increasing content of CaZrO3 additive. According to the thermodynamic calculation, an obvious increase in Gibbs free energy of formation for the BaZrO3 refractory was confirmed with the CaZrO3 additive, resulting in the increasing extent of the dissolution‐corrosion between the refractory and the titanium alloy melts.