Unfired magnesite-chrome bricks used for metallurgical non-ferrous smelting furnaces, and preparation method thereof

The invention discloses a high-grade refractory material used for metallurgical non-ferrous smelting furnaces, and a preparation method thereof, and more specifically relates to unfired magnesite-chrome bricks used for metallurgical non-ferrous smelting furnaces. The unfired magnesite-chrome bricks comprise a skeletal material, a powder material, and a binding agent; the skeletal material is composed of, by weight, 35 to 45 parts of high purity magnesia (MgO>=97.5%, and particle size ranges from 7 to 90 meshes), and 15 to 25 parts of fused magnesite chrome sinter (MgO>=69%, Cr2O3>=20%, and particle size ranges from 7 to 90 meshes); the powder material is composed of, by weight, 30 to 35 parts of chrome iron ore concentrate (Cr2O3 content ranges from 47 to 60%, Fe2O3 content ranges from 15 to 27%, MgO content ranges from 9.0 to 13%, and particle size ranges from 300 to 350 meshes), 2 to 4 parts of a cold sintering agent (nano-grade particle size), 0.3 to 0.6 part of a rare earth oxide (particle size ranges fro