Spodumene glass-ceramics with low thermal expansion coefficient prepared using gold tailings

Spodumene glass-ceramics composed of Li₂O-Al₂O₃-SiO₂ were prepared using gold tailings (Shuangqi Mountain, Quanzhou, Fujian, China) as the raw material through a two-step crystallization method. The crystallization behavior, phase structure, and microstructure of the glass-ceramics were characterized by DSC, XRD, and SEM. The results indicate that the addition of gold tailings promoted the precipitation of the β-quartz solid solution and its transformation into β-spodumene solid solution. Dense nanoscale crystal particles have been formed in the crystallized samples, and a high content of gold tailings significantly improved the flexural strength and thermal conductivity of glass-ceramics. Simultaneously, low coefficient of thermal expansion can be obtained at higher crystallization temperatures. Overall, the sample fabricated with 45% gold tailings showed relatively excellent properties at a crystallization temperature of 850 ℃. The coefficient of thermal expansion (CTE), flexural strength, bulk density, and thermal conductivity are 2.38 × 10^− 6 K^− 1, 87.71 MPa, 2.445 kg m⁻³, and 3.574 W m^− 1K^− 1 (500 °C), respectively. This work verifies the possibility of using gold tailings as raw materials for the preparation of lithium spodumene glass-ceramics, which have potential for large-scale commercial applications.