Constitution of laser melted Al2O3–MgO–SiO2ceramics

Abstract

An investigation has been made of ceramics of the Al2 O3–MgO–SiO2 system produced as pellets by laser melting of powder mixtures of the component oxides, followed by relatively rapid solidification. The phase constitution and microstructural features have been investigated using X-ray diffraction, microscopy, and differential thermal analysis. Compositions were selected with the aim of determining the solidification sequences, including certain invariant reactions involving combinations of the silica, cordierite, mullite, protoenstatite, forsterite, and periclase phases. Taking account of compositional changes that occurred during melting, and the fact that glass formation interrupted the solidification sequences, the observations were generally consistent with existing phase diagram data.MST/3120