Magnesium-chromium composite spinelle brick

Abstract

The invention discloses a magnesium-chrome composite spinel brick which is made from synthetical magnesium-chrome spinel sand, magnesia, chromium concentrate and chrome oxide according the weight percentages as follows: taking 65 percent to 70 percent of MgO, 20 percent to 25 percent of Cr2O3, 0.5 percent to 1.2 percent of SiO2, 4 percent to 6 percent of Fe2O3, 2 percent to 4 percent of Al2O3 and 0.5 percent to 1.2 percent of CaO to the material of the number one synthetical magnesium-chrome spinel sand; taking 55 percent to 60 percent of MgO, 30 percent to 35 percent of Cr2O3, 0.5 percent to 1.2 percent of SiO2, 4 percent to 6 percent of Fe2O3, 2 percent to 4 percent of Al2O3 and 0.5 percent to 1.2 percent of CaO to the material of the number two synthetical magnesium-chrome spinel sand; taking 70 percent to 75 percent of MgO, 14 percent to 19 percent of Cr2O3, 0.8 percent to 1.2 percent of SiO2, 4.5 percent to 7 percent of Fe2O3, 2 percent to 4 percent of Al2O3 and 0.8 percent to 1.5 percent of CaO to the material of the number three synthetical magnesium-chrome spinel sand; taking 97 percent to 98.5 percent of MgO, 0.5 percent to 1.3 percent of SiO2, 0.5 percent to 1.3 percent of CaO and 0.2 percent to 0.5 percent of Fe2O3 to the material of the magnesia; taking 50 percent to 60 percent of Cr2O3, 9 percent to 15 percent of MgO, 0.3 percent to 1.5 percent of SiO2, 15 percent to 25 percent of Fe2O3 and 8 percent to 15 percent of Al2O3 to the material of the chromium concentrate; taking 92 percent to 96 percent of Cr2O3 and 4 percent to 8 percent of ZrO to the material of the chrome oxide. The invention has the advantage of having the characteristics of compact structure, thermal shock resistance, anti-scaling off, erosion resistance etc.

Description

technical field [0001] The invention relates to refractory bricks for industrial kilns, in particular to magnesia-chromium composite spinel bricks for industrial kilns such as RH furnaces, AOD furnaces, and VOD furnaces. Background technique [0002] The refractory bricks used in industrial kilns such as RH furnaces, AOD furnaces, and VOD furnaces outside the furnace are required to have a compact structure and have good thermal shock resistance, corrosion resistance, and peeling resistance. my country has been relying on imports for a long time, which directly leads to the increase of production costs. Contents of the invention [0003] The purpose of the present invention is to provide a high-density, magnesia-chromium composite spinel brick with good spalling resistance. [0004] To achieve the above object, the present invention can take the following technical solutions: [0005] The magnesia-chromium composite spinel brick of the present invention is prepared by syn...

AI Technical Summary

Problems solved by technology

[0002] The refractory bricks used in industrial kilns such as RH furnaces, AOD furnaces, and VOD furnaces outside the furnace are required to have a compact structure and have good thermal shock resistance, corrosion resistance, and peeling resistance. The service life of permanent refractory materials, my country has been relying on imports for a long time, which directly led to the increase of production costs