熔融法制备金矿尾砂微晶玻璃及性能测试

以金矿尾砂、方解石为主要原料,添加其它所需原料为硼砂、ZnO、Cr2O3、Sb2O3等,采用熔融法制备CaO-Al2O3-SiO2系微晶玻璃.利用硅碳棒炉在1 300℃~1 350℃下保温4h熔制玻璃,熔好的玻璃液浇注在事先预热的不锈钢模具上,成形后放入马弗炉在600℃保温1h退火处理,对玻璃试样热处理得到微晶玻璃样品.采用TG-DSC差热分析仪测定基础玻璃的DSC曲线,确定金矿尾砂微晶玻璃较佳的热处理工艺为:800℃保温2h进行核化处理,890℃保温3h进行晶化处理.通过XRD、SEM等分析手段对试样的物相及微观结构进行了分析,测定制得微晶玻璃的抗折强度、热膨胀系数、体积密度等性能.结果表明:制得金矿尾砂微晶玻璃的主晶相为:辉石和透辉石固溶体,样品的热膨胀系数为69.5×10-7/℃,抗折强度为119.2MPa,体积密度为2.81g/cm3.

Preparation of glass-ceramics from gold tailing by melting method and measured its properties

The CaO-Al2O3-SiO2 glass-ceramics from gold tailing as mainly raw material and other additives such as borax, Cr2O3, Na2SiF6, Sb2O3 were prepared by melting method. The mixed powders were melted using silicon carbide furnace at 1 300 ℃-1350 ℃ for 4 h, then the melt was cast on preheated steel, the glass samples were annealed in the muffle at 600 ℃ for 1 h. The glass ceramics were prepared by heated the basic glass. The DSC curve of basic glass was measured by differential thermal analysis （TG-DSC） to determine the heat treatment processes of the glass ceramics. The crystals and microstructures of the specimens were analyzed by XRD and SEM. The thermal expanding coefficients, bending strengths and densities of the samples were measured. The results show that the good heat treatment process of the glass-ceramics is at 820 ℃ for 2 h and 900 ℃ for 3 h, the main crystals were augites and diopside solid solutions, the thermal expanding coefficient of the specimen was 62.5×10^-7/℃, the bending strength was 119.2 MPa, the density is 2.81g/cm3.