Abstract:Copper smelting slag tailings are solid wastes obtained from flotation depletion of copper slag generated in pyrometallurgical copper smelting. Their massive accumulation produces serious environmental and safety hazards. Forsterite-spinel composite materials were prepared by a high-temperature solid-state sintering method using copper smelting slag tailings as the main raw material, with addition of light-burned magnesia and activated alumina. Effects of sintering temperature on phase composition, microstructure, and physical properties of the materials were systematically investigated. Results showed that the main crystalline phases of sintered samples were forsterite and spinel, while fayalite phase was completely decomposed. As sintering temperature increased, grains of forsterite and spinel gradually grew, and densification degree of the material continuously improved. When sintering temperature was 1 400 ℃, the sample exhibited the best comprehensive performance, with a bulk density of 2.75 g/cm3, an apparent porosity of 24.11%, and a cold compressive strength of 138.5 MPa.