The "Direct Bond" In Magnesia Chromite And Magnesia Spinel Refractories

The microstructures of several commercial refractory bricks have been characterised using scanning and transmission electron microscopy. The "direct bond" is shown to be direct at the level of resolution attainable (~0.3nm), and a significant number of such direct contacts occur between non-silicate phases in the microstructures of magnesia-chromite bricks. However, attempts to examine the direct bond in magnesia-spinel bricks were unsuccessful due to nonuniform ion thinning of TEM specimens.