利用废陶瓷辊棒制备堇青石陶瓷材料

Preparation of cordierite ceramics using ceramic roller waste

利用废陶瓷辊棒作为主要原料采用高温煅烧法制备堇青石陶瓷材料,研究了烧成工艺对堇青石材料的晶相、显微结构和性能的影响。利用X射线衍射仪表征试样的晶相结构;利用扫描电子显微镜观察试样的显微结构;利用排水法测试试样的显气孔率和体积密度;通过万能试验机检测试样的抗弯强度。研究结果表明:试样经煅烧后形成堇青石陶瓷材料,主晶相为堇青石相,次晶相为镁铝尖晶石相。堇青石呈粒状分布,试样中具有一定量的玻璃相,均匀地分布着微米级的微孔。随着煅烧温度和保温时间的增加,显气孔率先减小后增大,体积密度先增大后减小,抗弯强度先增大后减小,最佳烧结工艺为煅烧温度1 350℃保温时间3 h时,显气孔率最小为21%,体积密度为1.96 g/cm3,抗弯强度最大为58 MPa。

In this study,cordierite ceramics was prepared by high temperature sintering using ceramic roller waste as raw materials. The effects of sintering process on the crystalline phases,microstructure and properties of cordierite samples were investigated. X- ray diffraction was carried out to characterize the crystalline structure of samples. The microstructure morphology of the sintered samples was observed by a scanning electron microscope. The apparent porosity and bulk density of the samples were measured using Archimedes＇ s method. Mechanical testing machine was employed to evaluate the bending strength of the specimen. The results show that the primary crystalline phase of cordierite ceramics obtained by sintering is cordierite,whereas the secondary crystalline phase of which is spinel. The cordierite crystals are in granular shape and bonded by glassy phase with micropores being uniformly distributed in the samples. As the sintering temperature and maintaining time increase,the apparent porosity of the samples first decreases and then increases,and the bulk density and bending strength of the samples first decrease and then increase. The optimal sintering properties are obtained at a sintering temperature of 1350℃ maintained for 3 h with an apparent porosity of 21 %,a bulk density of 1. 96 g / cm3 and the maximum bending strength of 58 MPa.