含锌钇铝硅酸盐玻璃的晶化特征和力学性能  

Crystallization Behavior and Mechanical Properties of Zinc-Containing Yttrium Aluminosilicate Glasses

作　　者：郑庆双 陈胜林 乔昂 王觅堂 陶海征[1] ZHENG Qingshuang;CHEN Shenglin;QIAO Ang;WANG Mitang;TAO Haizheng(State Key Laboratory of Silicate Materials for Architectures,Wuhan University of Technology,Wuhan 430070,China;School of Materials and Chemistry,University of Shanghai for Science and Technology,Shanghai 200093,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430070 [2]上海理工大学材料与化学学院,上海200093

出　　处：《硅酸盐学报》2024年第8期2495-2501,共7页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金(52172007,51974168,51662033);江苏省碳达峰碳中和科技创新专项(BE2022035)。

摘　　要：因具有与碳化硅陶瓷相匹配的膨胀系数和良好的物化性能,钇铝硅酸盐(YAS)玻璃和玻璃陶瓷广受关注。为进一步提升YAS玻璃陶瓷的力学性能,以22Y_(2)O_(3)·19Al_(2)O_(3)·59SiO_(2)玻璃为基础,基于n(ZnO):n(Al_(2)O_(3))=2:1摩尔比,利用Zn O逐步替换Al_(2)O_(3),探索了系列含锌YAS玻璃的晶化特征和力学性能。通过选择合适的热处理工艺,制备了系列玻璃陶瓷。结果发现:ZnO的引入具有晶粒细化作用,随着ZnO含量的增加,析出晶粒的尺寸逐渐减小;通过合适的热处理,获得了最大断裂韧性为1.92 MPa·m^(0.5)的含锌YAS玻璃陶瓷;与原始无锌YAS玻璃陶瓷(1.16 MPa·m^(0.5))相比,提升了65%。上述工作为高性能玻璃陶瓷的研制提供了一种新的思路。Introduction Yttrium aluminum silicate(YAS)glass ceramics,known for their high-temperature resistance,excellent hardness,and mechanical strength,attract wide attention as coating materials for bonding or protecting silicon carbide ceramics.The precipitation of the y-Y_(2)Si_(2)O_(7) crystalline phase in YAS glass,particularly in comparison with SiC,is advantageous due to the matched coefficients of thermal expansion between y-Y_(2)Si_(2)O_(7) and SiC.This often leads to its use as a sintering aid or in anti-oxidation coatings for SiC.A glass composition with reported proportions of 22Y_(2)O_(3)-19Al_(2)O_(3)-59SiO_(2)(in mole)has been designed to selectively precipitate only the y-Y_(2)Si_(2)O_(7) crystalline phase through process engineering,achieving a softening temperature exceeding 1400℃.However,this glass composition initially undergoes a droplet-type phase separation,resulting in the precipitation of y-Y_(2)Si_(2)O_(7) crystals in regions enriched with Y_(2)O_(3) and SiO_(2).The large gap between these two phase-separated regions leads to non-uniform distribution of y-Y_(2)Si_(2)O_(7) grain sizes.The cross-sectional morphology exhibits a fibrous structure,which may affect the mechanical properties of the glass ceramics.Compared to fibrous structures,spherical grains have a higher stress distribution,providing the glass ceramics with greater strength.Previous studies have shown that TiO_(2) and CaF_(2) are unsuitable as nucleating agents for achieving uniform and fine grains in YAS glass.In this study,a base glass has a composition of 22Y_(2)O_(3)·19Al_(2)O_(3)·59SiO_(2),The addition of ZnO into the base glass was found to inhibit large-sized phase separation in YAS glass,resulting in a significant refinement of precipitated grain sizes.This led to a substantial improvement in the fracture toughness of the glass ceramics.By observing the crack propagation patterns in the glass ceramics,the toughening mechanism has been elucidated.Methods On the basis of the glass composition 22Y_(2)O_(3)·19Al_(2)O_(3)·

关 键 词：钇铝硅酸盐 玻璃陶瓷 断裂韧性 硬度 

分 类 号：TQ171.1[化学工程—玻璃工业]