【摘要】 采用DTA、XRD、SEM、热膨胀仪等仪器研究了晶化温度对Li2O-ZnO-Al2O3-SiO2微晶玻璃的物相组成以及热膨胀系数的影响。结果表明:在晶化温度为625℃时,微晶玻璃中析出βⅡ-Li2ZnSiO4晶相,650℃时又析出少量方石英晶相;随着晶化温度上升,方石英相逐渐转化为β-石英固溶体,至750℃时βⅡ-Li2ZnSiO4晶相开始转化为γ0-Li2ZnSiO4晶相;当温度高于800℃后,微晶玻璃中主要含有β-石英固溶体和γ0-Li2ZnSiO4两种晶相,并且晶粒尺寸变大;不同晶化温度下制得微晶玻璃的热膨胀系数在(72~119)×10-7℃-1(20~500℃)之间,随着晶化温度的升高,试样的热膨胀系数先升高而后下降,然后趋于平稳,在650℃达到最大。更多还原

【Abstract】 The effect of crystallization temperature on the phase composition and thermal expansion coefficient(TEC) of Li2O-ZnO-Al2O3-SiO2(LZAS) glass-ceramic was studied by means of DTA,XRD,SEM and thermal analyzer methods.The results show that the crystallization of βⅡ-Li2ZnSiO4 occurred after the glass was treated at 625 ℃,and cristobalite crystallite formed at 650 ℃;then β-quartz solid solutions replaced cristobalite crystallite gradually with the temperature increasing.The transformation from βⅡ-Li2ZnSiO4 to γ0-Li2ZnSiO4 took place at 750 ℃.The crystallization phases in the glass-ceramics obtained at the temperature higher than 800 ℃ were β-quartz solid solutions and γ0-Li2ZnSiO4,and the size of crystal particles increased gradually.The thermal expansion coefficient of the glass-ceramics which formed at different crystallization temperatures varied from 72×10-7 ℃-1 to 119×10-7 ℃-1 in the temperature range of 20-500 ℃,which increased first and reached to the maxinum at 650 ℃,then decreased and changed to be steady.更多还原