Structure and properties of dense periclase refractories prepared from laminated granules

Conclusions

On the basis of laminated granules we prepared dense periclase refractories with a higher thermal-shock resistance than that of ordinary articles prepared by sintering solid granules. The technical properties are determined by the degree of development of a fragmentary structure which depends on the size of the granules, the composition of their outside layer, and the composition of the bonding mass in the batch.

With an increase in the dimensions of the laminated granules and addition to the composition of their outside layers of yttrium oxide or lanthanum zirconate and to the composition of the batch of solid grains of periclase of a smaller fraction in the articles, complex elements are produced which form the fragments of the structure. This increases the thermal-shock resistance of the goods. The porosity of the articles is reduced with a reduction in the amount of dispersed part of the batch and its additional sintering with the formation of closed pores. The strength of the articles is reduced with a rise in the amount and size of the channel pores, and there is its increase during the formation of additional bonds in the area of contacts between the bond and the aggregates of coarse grains.