Na_(2)O对锂铝硅微晶玻璃析晶及性能的影响  

Effect of Na_(2)O on Crystallization and Properties of Lithium Aluminum Silicate Glass-Ceramics

作　　者：郑伟宏[1] 王启东 高子鹏 张浩[1] 袁坚[1] 田培静[1] ZHENG Weihong;WANG Qidong;GAO Zipeng;ZHANG Hao;YUAN Jian;TIAN Peijing(State Key Laboratory of Silicate Materials for Architectures,Wuhan University of Technology,Wuhan 430070,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

出　　处：《硅酸盐通报》2024年第4期1301-1307,共7页Bulletin of the Chinese Ceramic Society

基　　金：硅酸盐国家重点实验室(武汉理工大学)开放基金(2011DA105356)。

摘　　要：采用熔融法制备了不同Na_(2)O含量的透明锂铝硅微晶玻璃,通过DSC、XRD、FESEM等测试方法研究了不同Na_(2)O含量对玻璃析晶及性能的影响。结果表明:Na_(2)O的引入能显著降低玻璃的转变温度和析晶温度,抑制LiAlSi_(4)O_(10)晶相的析出。但Na_(2)O的引入促使微晶玻璃中析出Li_(2)Si_(2)O_(5)新相,并且随着Na_(2)O引入量的增加,Li_(2)Si_(2)O_(5)转变为主晶相。由于晶体尺寸均为纳米级,主晶相的转变对透过率影响较小,微晶玻璃的可见光透过率均高于85%。主晶相的转变有效增强了微晶玻璃的机械性能,其弯曲强度由300 MPa提升至331 MPa。Na_(2)O的引入有效增强了Na-K交换,Na_(2)O含量为4%(质量分数)的Li 2O-Al_(2)O_(3)-SiO_(2)微晶玻璃在410℃的KNO_(3)熔盐中交换6 h后,维氏硬度由7.108 GPa提升至7.403 GPa,弯曲强度由331 MPa提升至470 MPa。Transparent lithium aluminum silicon glass-ceramics with different Na_(2)O content was prepared by melting method,and the effect of different Na_(2)O content on the crystallization and properties of the glass were studied by DSC,XRD,FESEM and other test methods.The results show that the introduction of Na_(2)O can significantly reduce the transition temperature and crystallization temperature of glass,and inhibit the precipitation of LiAlSi_(4)O_(10) crystalline phase.However,the introduction of Na_(2)O leads to the precipitation of a new Li_(2)Si_(2)O_(5) phase in glass-ceramics,and with the increase of Na_(2)O content,Li_(2)Si_(2)O_(5) transforms into the main crystal phase.Since the crystal size is in the nanometer range,the change of main crystal phase has little effect on transmittance,and the visible light transmittance of glass-ceramics is higher than 85%.The transition of main crystal phase significantly enhances the mechanical properties of glass-ceramics,and the flexural strength increases from 300 MPa to 331 MPa.The introduction of Na_(2)O effectively enhances the Na-K exchange.When the LAS glass-ceramics with Na_(2)O content of 4%(mass fraction)exchanges in KNO 3 molten salt at 410℃ for 6 h,the Vickers hardness increases from 7.108 GPa to 7.403 GPa,and the flexural strength increases from 331 MPa to 470 MPa.

关 键 词：Na_(2)O LiAlSi_(4)O_(10) Li_(2)Si_(2)O_(5) Li_(2)O-Al_(2)O_(3)-SiO_(2)微晶玻璃 主晶相转变 Na-K交换 

分 类 号：TQ171[化学工程—玻璃工业]