SiO2含量对钛矿渣微晶玻璃晶化行为的影响

以钛矿渣为主要原料,采用熔融法制备CaO-MgO-Al₂O₃-SiO₂系微晶玻璃,通过综合热分析仪、X射线衍射仪和扫描电子显微镜分析了SiO₂含量对钛矿渣微晶玻璃的基础玻璃稳定性及晶化行为的影响。结果显示:以原渣制备微晶玻璃时,其基础玻璃结构不稳定,易析出钙钛矿晶体,随着SiO₂含量的增加,基础玻璃趋于稳定,析晶温度上升,热处理后析晶程度更高,显微结构更加致密,因而强度更高。通过加入辅助原料石英粉来调节SiO₂含量,当SiO₂含量为40%(质量分数)时,可以制备出具有稳定玻璃体、晶相仅为透辉石、抗弯强度为82.1 MPa的微晶玻璃,其钛矿渣掺量在80%(质量分数)以上,具有重要的经济与社会效应。

Effect of SiO2 Content on Crystallization Behavior of Titanium Slag Glass-Ceramics

Using titanium slag as the main raw material, the CaO-MgO-Al₂O₃-SiO₂ series glass-ceramics were prepared by the melting method. Through integrated thermal analyzer, X-ray diffractometer, and scanning electron microscopy, the effect of SiO₂ content on the stability and crystallization behavior of the base glass of titanium slag glass-ceramics was analyzed. The results show that when the original slag is used to prepare glass-ceramics, the structure of the basic glass is unstable, and perovskite crystals are easy to precipitate. With the increase of SiO₂ content, the basic glass tends to be stable, the crystallization temperature increases, and the degree of crystallization after heat treatment becomes higher, the microstructure is denser and therefore the strength is higher. The SiO₂ content is adjusted by adding the auxiliary raw material quartz powder. When the SiO₂ content is 40% (mass fraction), glass-ceramics with stable glass body, crystal phase only diopside, and bending strength of 82.1 MPa are prepared. The content of titanium slag is more than 80%(mass fraction), which has important economic and social effects.