CaO对六盘水地区玄武岩熔体性质的调节研究

Effect of CaO on Melting Properties of Basalt in Liupanshui Area

玄武岩的熔体特性对玄武岩纤维的拉丝及其性能具有直接影响,因此以六盘水地区玄武岩为研究对象,利用高温水冷法、X射线衍射、红外光谱以及热力学软件FactSage计算研究CaO对该地区玄武岩熔体性质的影响。研究结果表明:随着CaO添加量的增加,玄武岩的流动温度先降低,然后保持稳定,最后升高。当CaO添加量为15%、35%以及45%时,玄武岩的流动温度分别为1190℃、1184℃以及1250℃;随着CaO添加量的增加,玄武岩的完全熔化温度先降低后升高,当CaO添加量为15%时,玄武岩的完全熔化温度降为最低的1163.55℃;CaO添加量范围为15%~25%时,玄武岩能够形成包含透辉石、硅灰石以及钙铝黄长石等物相的低温共熔体系,熔体的结构聚合度降低,使得玄武岩的流动温度和完全熔化温度降低;CaO添加量范围为25%~45%时,玄武岩低温共熔体系中的透辉石、硅灰石等物相不断减少,而钙铝黄长石不断增多,使得玄武岩的流动温度和完全熔化温度升高;结合酸度系数及相图分析得知,CaO添加量范围为15%~25%时,有利于制备玄武岩纤维。

The melt properties played an important role in basalt fibers production. Therefore, the CaO were added in the basalt to adjust the properties of basalt melts. The properties of basalt melts were calculated and analyzed by water-quenching method, XRD, FTIR and thermodynamic software FactSage respectively. The results show that with the increase of CaO dosage, the flow temperature of basalt decreases firstly then remains stable, and rises finally. When CaO dosage is 15%, 35% and 45%, the flow temperature of basalt is 1190 ℃, 1184 ℃ and 1250 ℃, respectively. With the increase of CaO dosage, the complete melting temperature of basalt firstly decreases and then increases. When the CaO dosage is 15%, the complete melting temperature of basalt is the lowest 1163.55 ℃. When the CaO dosage ranges from 15% to 25%, the eutectic system which containing diopside, wollastonite and feldspar phases form in basalt. The structural polymerization degree of the melt decreases, which make the flow temperature of basalt lower. When CaO dosage ranges from 25% to 45%, the phases of diopside and wollastonite in basalt eutectic system decrease continuously, while the flow temperature and complete melting temperature of basalt increase with the increase of feldspar. Combined with acidity coefficient and phase diagram analysis, the range of CaO dosage is 15%-25%, it is more advantageous to prepare basalt fibers.