Abstract: Coal gangue and waste glass were used as main raw materials to prepare foamed ceramics. The effects of calcination temperature and content of Na₃PO₄ on phase structure, apparent porosity, compressive strength and apparent density of foamed ceramics were studied. The results show that, as the calcination temperature increases, the linear expansion rate of foamed ceramics samples gradually increases, while the apparent density gradually decreases. The average pore diameter and apparent porosity of foamed ceramics gradually increase and the compressive strength decreases as the calcination temperature or the Na₃PO₄ content increases, while the apparent density shows different trends and the crystallite structure of the sample changes very slightly. By optimizing the preparation conditions, it is found that when the content of Na₃PO₄ is 3% (mass fraction) at the calcination temperature of 1 140 ℃, the prepared foamed ceramics exhibits uniform pore structure with the average pore diameter of 0.92 mm, the compressive strength reaches as high as 4.72 MPa, and the apparent density achieves 0.69 g/cm³. The preparation process of foamed ceramics based on coal gangue is simple and the cost is low, which provides a feasible way for the utilization of coal gangue resources.

Key words: foamed ceramics, coal gangue, waste glass, calcination temperature, Na₃PO₄, pore structure