Fe2+、Fe3+对CaO-Al2O3-SiO2-MgO系微晶玻璃析晶性能的影响规律

为了利用大量的含铁铝硅酸盐固体废弃物制备具有高附加值的微晶玻璃，采用DTA、XRD、SEM、EDS等手段研究了Fe₂₊、Fe₃₊对CASM系微晶玻璃析晶性能的影响，结果表明，Fe₂₊在微晶玻璃中与Mgz+的作用相同，取代以网络外体形式存在的Al₃₊，使得微晶玻璃的析晶温度逐渐下降，而对析晶能力几乎没有影响，并当Fe₂₊掺入量为2%时，主晶相由铝黄长石转变为镁黄长石，在7.5%时，进一步转变为透辉石．Fe₃₊掺量小于7.5%时，起到补充S14不足的作用，当大于7.5%时，部分Fe₃₊起到与Fe₂₊、Mg₂₊相同的作用，使得析晶温度呈先升后降的变化，在掺量为7.5%时，铝黄长石主晶相才开始转变为镁黄长石，在10%对，转变为透辉石，且析晶能力得到大幅提升．随着Fe₂₊和Fe₃₊含量增加，虽然微晶玻璃中主晶相的变化顺序相同，但Fe₂₊具有降低微晶玻璃析晶温度的作用，而一定量的Fe₃₊可作为晶核剂提高微晶玻璃的析晶能力

The influence of Fe2+ and Fe3+ on crystallization of CaO-Al2O3-SiO2-MgO system glass-ceramics

To prepare the glass-ceramics with high-additional-value using aluminosilicate solid waste containing iron ,the influence of Fe₂₊ and Fe₃₊ on crystallization property of CASM system glass-ceramics was investigatedby means of DTA,XRD,SEM and EDS. The results indicate that the Fe₂₊ ,or the Mgz+ ,could replace the Al₃₊existing as the network modifier,so the crystallization temperature of glass-ceramics gradually decreases,andthe main crystal phase of glass-ceramics transforms from the gehlenite into the akermanite when Fe₂₊ content is2. Owt% ,then transforms into the diopside when it is 7. 5wt% . However,crystallization ability is hardly affect-ed by Fe₂₊. The Fe₃₊ exists as the network former and plays the supplement lack of Sj4+ role under 7. 5wt% .But when the Fe₃₊ content is higher than 7.5wt% ,a part of Fe₃₊ ,or the Fe₂₊ and Mg₂₊ ,exists as the networkmodifier. The crystallization temperature gradually increase at first and then decrease. Although the transforma-tion sequence of main crystal phase is the same for the CASM system glass-ceramics with the increase of Fez+and Fe₃₊ content,the Fe₂₊ has the ability to decrease the crystallization temperature,and the Fe₃₊ could im-prove the crystallization ability as the nucleating agent