二氧化钛对镁铝硅微晶玻璃析晶行为与性能的影响  

Effect of Titanium Dioxide on Crystallization Behavior and Properties of MgO–Al_(2)O_(3)–SiO_(2) Glass–Ceramics

作　　者：余炜 梁新辉 李书志 高文凯 张占蒙 钟波 王静[1] 韩建军[1] YU Wei;LIANG Xinhui;LI Shuzhi;GAO Wenkai;ZHANG Zhanmeng;ZHONG Bo;WANG Jing;HAN Jianjun(State Key Laboratory of Silicate Materials for Architectures,Wuhan University of Technology,Wuhan 430070,China;Xianning SG photoelectric glass Co.Ltd.,Xianning 437100,Hubei,China)

机构地区：[1]武汉理工大学,硅酸盐建筑材料国家重点实验室,武汉4300702 [2]咸宁南玻光电玻璃有限公司,湖北咸宁437100

出　　处：《硅酸盐学报》2022年第5期1283-1291,共9页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金(52072278);中央高校基础研究经费项目(WUT:2021ZVA124)。

摘　　要：堇青石微晶玻璃具有低介电常数、低介电损耗、低热膨胀等优点,化学计量堇青石Mg O–Al_(2)O_(3)–SiO_(2)(MAS)玻璃组成易表面析晶。采用熔融–整体析晶法制备了MAS微晶玻璃,研究了TiO_(2)添加量对MAS微晶玻璃析晶行为和性能的影响。随着TiO_(2)添加量的增加,玻璃化转变温度和第1析晶峰温度降低,说明TiO_(2)能够有效促进析晶。Ti O_(2)进入玻璃网络结构中,促进玻璃中先形成μ-堇青石和钛酸镁铝相,在较高温度下转变为α-堇青石。当x(TiO_(2))>5%(摩尔分数)时玻璃结晶机制为体析晶。当TiO_(2)含量增加到10%时,经800℃保温10 h+1000℃保温5 h热处理的微晶玻璃具有高密度2.95 g/cm^(2),高硬度9.67 GPa,高热导率2.13 W/(m·K)。在频率为8.2~12.4 GHz,其介电常数为6.3~6.5,介电损耗在10^(-2)~10^(-3)内波动,在频率为1 MHz,介电常数为10.8,介电损耗为0.0244。Cordierite glass–ceramics exhibit low dielectric constant,dielectric loss and thermal expansion.The stoichiometric cordierite MgO–Al_(2)O_(3)–SiO_(2)(MAS)glass is due to the surface crystallization.In this paper,MAS glass–ceramics with various contents of TiO_(2)as a nucleation agent were prepared by a melting method and subsequent heat treatment.The effect of TiO_(2)content on the crystallization behavior and properties was investigated.The results show that the glass transition temperature and the first crystallization peak temperature decrease with the increase of TiO_(2)content,indicating that TiO_(2)can effectively promote the crystallization.TiO_(2)enters into the glass network structure,and facilitates the formation ofμ-cordierite and magnesium aluminum titanate crystalline phases in the glass,and then formα-cordierite at a higher temperature.The crystallization mechanism of glass with more than 5%(in molar fraction)TiO_(2)becomes the bulk crystallization.As Ti O_(2)content increases to 10%,the glass–ceramics heat-treated at 800℃for 10 h and 1000℃for 5 h have a high density of 2.95 g/cm^(3),a hardness of 9.67 GPa,and a thermal conductivity of 2.13 W/(m·K).At 8.2–12.4 GHz,its dielectric constant is 6.3–6.5 and the dielectric loss fluctuates from 10^(-2)to 10^(-3).At 1 MHz,the dielectric constant is 10.8 and the dielectric loss is 0.0244.

关 键 词：微晶玻璃 堇青石 表面析晶 介电性能 二氧化钛 

分 类 号：TQ171[化学工程—玻璃工业]