Abstract

Use CaO-Al₂O₃-SiO₂ glass-ceramics from gold tailings in Hanyin as main raw materials, which were prepared by a melting method. In this paper, the effects of nucleation temperature and crystallization temperature on microstructures and properties of the glass-ceramic specimens were investigated. The thermal property of the glass-ceramics was discussed by differential scanning calorimetry (DSC), and microstructure was characterized by X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). Methods of a 4-point bending strength test, DIL-402C dilatometer and Archimedes method were used to determine the bending strength, thermal expanding coefficient and density of glass-ceramics. The experiment results indicated that the optimal properties of glass-ceramics were obtained by nucleation at 800 °C for 2 h, and then crystalling at 950 °C for 3 h. XRD analyses demonstrated that the main phase of gold tailings glass-ceramics was augite and diopside (CaMgSi₂O₆), and the minor phase was potassium iron silicate (KFeSi₂O₆). The bending strength, density and thermal expanding coefficient of the glass-ceramics were 128 MPa, 2.840 g/cm³ and 7.85 × 10⁻⁶/°C, respectively.

摘要

使用 CaO-Al ₂ O ₃ -SiO ₂以汉阴金尾矿为主要原料，采用熔融法制备微晶玻璃。本文研究了成核温度和结晶温度对微晶玻璃显微组织和性能的影响。通过差示扫描量热法（DSC）讨论微晶玻璃的热性能，并通过X射线衍射（XRD）和扫描电子显微镜（SEM）表征微观结构。采用四点弯曲强度试验方法、DIL-402C膨胀计和阿基米德法测定微晶玻璃的弯曲强度、热膨胀系数和密度。实验结果表明，微晶玻璃的最佳性能是在 800 ℃下成核 2 h，然后在 950 ℃下结晶 3 h 获得的。₂ O ₆ )，次要相是硅酸铁钾(KFeSi ₂ O ₆ )。微晶玻璃的弯曲强度、密度和热膨胀系数分别为128 MPa、2.840 g/cm ³和7.85×10 ^-6 /°C。