CHARACTERIZATION OF MAGNESIA AND MAGNESIA-CHROMITE BRICKS BY THE USE OF DIFFERENT DESTRUCTIVE AND NON DESTRUCTIVE TESTING METHODS

摘要

Magnesia and magnesia-chromite refractory bricks have a wide field of applications in the steel and non ferrous metal industry. Due to the use of these bricks in the highest wear areas, they are characterized by high refractoriness and good resistance to slag corrosion. For quality management purpose the physical properties (e.g. density, open porosity, cold crushing strength), which are measured at room temperature, are determined in a high frequency. The behavior at application temperature (1200℃ up to 1750℃) cannot be determined exacty with these measurements. Especially the characterization at operation conditions gives a better understanding on wear resistance. Properties, which have a high impact on in-service performance, like thermal shock resistance, modulus of elasticity and hot modulus of rupture are investigated in detail. The analytical methods are compared for specific magnesia and magnesia-chromite brick qualities. The correlation of all tested destructive and non destructive properties at room temperatures and different application temperatures, helps to select the best lining concept for the individual applications.