碱金属氧化物对MgO_Al_2O_省略__2系统微晶玻璃析晶和性能的影响_卢安贤.pdf

39 1 () Vol.39 No.1 2008 2 J. Cent. South Univ. (Science and Technology) Feb. 2008 MgO-Al O -SiO 2 3 2 ( 410083) (DSC)X (XRD)(SEM) (Li O Na O)Li O Na O MgO-Al O -SiO 2 2 2 2 2 3 2 Li O Na O ()3.6%Li O 1.8% 2 2 2 −6 ε 5.5tan σ2.1 α-5.1110 r −4 + + 10 Li Na 950 900 Li2O Li2O TQ171.73 A 1672-7207(2008)01−0042−06 Effects of alkalis on crystallization and properties of MgO-Al O -SiO system glass ceramics 2 3 2 LU An-xian, WANG Yu, XIAO Zhuo-hao (School of Materials Science and Engineering, Central South University, Changsha 410083, China) Abstract: Effects of Li O substitution for Na O on crystallization, thermal expansion coefficient and dielectric properties 2 2 of MgO-Al O -SiO system glass ceramics were studied at the condition of constant total content of alkalis(Li O+Na O) 2 3 2 2 2 using differential scanning calorimetry(DSC), X-ray diffraction (XRD) and scanning electron microscope(SEM). The results