TiO_2对熔融态高炉渣微晶玻璃析晶及性能的影响

Effect of TiO_2 on Crystallization and Property of Glass-ceramics from Molten Blast Furnace Slag

以熔融态高炉渣为主要原料,SiO_2、Al_2O_3、MgO和TiO_2等化学试剂为辅助原料,采用熔融法制备了以透辉石、普通辉石和钙镁黄长石为晶体的高炉渣微晶玻璃。通过DSC、XRD、SEM研究了晶核剂Ti O2对高炉渣微晶玻璃的析晶行为、晶相组成、显微结构和性能的影响。结果显示,随着TiO_2含量的升高,微晶玻璃的形核结晶温度降低,主晶相种类没有变化,但晶体含量增加,晶体形态由球状逐步发育成柱状、枝状、块状,最后成为疏松的块状晶。当TiO_2的加入量为4%时,微晶玻璃的性能达到最佳,此时体积密度为2.82 g/cm^3,吸水率0.03%,耐酸腐蚀性99.71%,耐碱腐蚀性99.98%。但过高的TiO_2含量(大于4%)会降低微晶玻璃性能。

The glass-ceramics with the diopside, augite and akermanite-gehlenite as the crystalline phase were prepared by melting method using blast furnace slag as the main raw materials, SiO2、Al2O3、MgO and TiO2 et al as auxiliary materials. Effect of TiO2 on the crystallization behavior, microstructure and properties of glass-ceramics from blast furnace slag were analyzed by DSC, XRD, SEM and other methods. The results showed that the nucleation and crystallization temperature of glass-ceramics decreased with the increase of the TiO2 content. Also the main crystal phase constituent was unchanging while the content of TiO2 increased. The crystal morphology changed from spherical grains to prismatic, dendritic, bulk and finally to a loose bulk crystal. The increase of Ti O2 can promote crystallization of the glass-ceramics. The glass-ceramics with the highest density（2.82 g/cm3）, minimum absorption（0.03%）, good acid and alkali corrosion resistance（99.71% and 99.99%） were obtained when the addition of TiO2 was 4%. However, the excessive TiO2 content（〉4%） would worsen the properties of the glass-ceramics.