烧结法制多孔玻璃陶瓷的微观结构和性能研究

Research on the Microstructure and Properties of Porous Glass-Ceramics using Powder-Sintering Method

以伟晶石为原料，采用粉末烧结法制备了SiO2-Al2O3-CaO-ZnO-R2O系统多孔玻璃陶瓷．运用热重／差热分析（TGA／SDTA）、X射线衍射（XRD）、扫描电镜（SEM）等技术对多孔玻璃陶瓷的性能、微观结构和组织进行了研究．结果表明：多孔玻璃陶瓷的主晶相为副硅灰石（单斜晶系），副晶相为钙长石（三斜晶系）；硬脂酸在100～490℃的范围内分解并挥发，使玻璃陶瓷体中形成了丰富的微米级闭合孔和少数的微米级半通孔，这些孔均匀分布在玻璃陶瓷体中．多孔玻璃陶瓷的密度约为2．3g／cm^3，孔隙率约为19％，维氏硬度随基础玻璃化学组成中SiO2与CaO比值（质量比）的增大而增大．

Based on the SiO2-Al2O3-CaO-ZnO-R2O system, pegmatite was used as a raw material to produce a new type porous glass-ceramics by a powder-sintering method. The properties, microstructures and textures of the porous glass-ceramics have been investigated by thermogravimetric analysis/diffenential thermal analysis（TGA/SDTA）, X-ray diffraction（XRD）, scanning electron microscopy（SEM） methods et al. Some conclusions can be gotten： parawollastonite （cli- norhombic system） is found as the main crystal phase and the anorthite （anorthic system） is observed as the paracrystalline phase in this new glass-ceramics material. A lot of micron dimension closed pores and several semi-open pores are uniformly formed and distributes in the glass-ceramics matrix because of the decomposition of stearic acid at 100-490℃. The bulk density of the sample is about 2.3 g/cm^3 , the porosity is about 19%, and the Vickers-hardness increases along with the growth of SiO2-to-CaO ratio（by mass） of the raw materials.