A SCANNING ELECTRON-MICROSCOPE STUDY OF REFRACTORY STRUCTURES

We have studied the structure of pure periclase refractories using a scanning electron microscope. The size of the crystals and aggregates and their spatial arrangement, and the features of the structure of the contact points between the aggregates in individual crystals, have been studied. The effect of additions of ZrO2 and chrome spinel on the recrystallization of the periclase has been established; the character of the pores in refractories obtained from sintered and fused materials has been shown. These studies have suggested that the high thermal-shock resistance of the articles made from sintered MgO is clearly determined by the formation of twisted, channel pores and a fragmentary structure, while the thermal-shock resistance of the articles made from fused materials is determined by the particular structure of the periclase powder grains and by the presence of large, elongated, randomly arranged periclase crystals. © 1980 Plenum Publishing Corporation.