氧化铋对微晶玻璃的相转变和性能的影响

为研究Bi2O3在堇青石基微晶玻璃烧结中的作用及其添加量对微晶玻璃的相转变和性能的影响,采用烧结法制备了不同Bi2O3含量的微晶玻璃,并对其进行了X射线衍射分析、显微分析和性能测试.结果表明:Bi2O3的加入降低了堇青石的u相向a相转变的温度,并有效促进微晶玻璃的烧结致密化;烧结样品的介电常数和抗折强度均随着Bi2O3加入量的增加而增加,且与密度变化规律相似;当Bi2O3添加量(质量分数)达5%时样品的介质损耗因子最低(＜10-3);微晶玻璃烧结样品的热膨胀系数基本符合线性规律.

Effect of Bi2O3 on the phase transformation and properties of glass ceramics

Cordierite-based glass ceramics containing different amounts of Bi2O3 were prepared by the sintering method. The effect of Bi2O3 on the phase transformation, sintering and property of cordierite-based glass ceramics was studied using XRD, SEM,thermal dilatometer and impedance analyzer. The results showed that the addition of Bi2O3 could lower the phase transformation temperature from u-to a- cordierite and enhance the densification of cordierite-based glass. The dielectric constant and the flexural strength of samples increased with the addition of Bi2O3 in a similar way as that of the density. With the addition of 5wt% Bi2O3, the dissipation factor of the sample showed the lowest value (<10-3). The thermal expansion coefficients of the samples with different amounts of Bi2O3 exhibit the characteristic of linearity.