Fused hercynite-corundum composite material and preparation method thereof

Abstract

The invention relates to a fused hercynite-corundum composite material and a preparation method thereof. The technical scheme is achieved by the following steps: firstly, using 34-44 wt% of Fe2O3 powder, 55-65 wt% of Al2O3 powder and 0.5-3 wt% of caustic-calcined magnesite powder as mixture, additionally adding 0.5-4 wt% of carbon powder of mixture; or, additionally adding 0.5-3 wt% of a bonding agent of mixture, uniformly stirring, drying a formed green body and then placing into a three-phase electric arc furnace, or directly uniformly stirring the raw materials and then placing into the three-phase electric arc furnace; secondly, fusing by adopting voltage of 90-220v, continuously smelting for 25-60min after all raw materials are smelted; or cooling smelted high-temperature synthesizedmaterials into the electric arc furnace for 24-48h, or guiding the smelted high-temperature synthesized materials into a water-cooling tank and cooling for 23-46h to obtain the hercynite-corundum composite material. The product prepared by the invention is the fused hercynite-corundum composite material comprising phase compositions of 80-98wt% of hercynite, 1-18wt% of corundum and 0.3-3wt% of magnesium aluminate spinel.

Description

technical field [0001] The invention belongs to the field of electric melting refractory materials. In particular, it relates to an electric fused iron-aluminum spinel-corundum composite material and a preparation method thereof. Background technique [0002] Magnesia-chrome bricks have been widely used in cement kilns due to their excellent high-temperature performance and good kiln skin-hanging performance. However, in high-alkaline environments, trivalent chromium ions will be converted into toxic hexavalent chromium ions, which are easy to pollute water sources. , and carcinogenic, with the enhancement of environmental awareness and the improvement of corresponding regulations, the development of magnesia-chrome bricks for cement kilns has been greatly restricted. Therefore, chromium-free has become the development trend of refractory materials for cement kilns. Magnesium-alumina spinel bricks and magnesium-iron spinel bricks are two important alternative materials. The...

AI Technical Summary

Problems solved by technology

There are few reports on the preparation of iron-aluminum spinel by electrofusion, such as Al 2 o 3 When iron-aluminum spinel is prepared by electromelting with Fe as raw material (Journal of Magnetism and Magnetic Materials, 2003, 264: 264-274), the reaction process is difficult to control and the reaction is not sufficient; to analyze pure Al 2 o 3 powder, analytically pure Fe 2 o 3 When powder and iron scale are used as raw materials to prepare iron-aluminum spinel by electromelting (Silicate Bulletin, 2007, 26(5): 1003-1006), although the process is simple, the analytically pure Al 2 o 3 powder and analytically pure Fe 2 o 3 Powder price is too high, resulting in too high cost, not suitable for large-scale industrial production

There are many reports on the synthesis of iron-aluminum spinel by sintering method, most of which are fired under the protection of atmosphere, such as "a synthetic iron-aluminum spinel and its preparation method (CN200510019267.6)" using buried carbon method to synthesize iron-aluminum Spinel, the process is labor-intensive, the atmosphere is difficult to control, and it is not easy for large-scale industrial production

The mechanical alloying method generally requires two steps of planetary grinding and calcination, the process is complicated, and it is not easy for industrial production (Materials Chemistry and Physics, 2002, 76: 104-109)