Studies in Clay Mixtures for Glass Melting Pots. Part 1V The Corrosion Resisting Properties

JSGT 1932 V16 T131-T144

A technique is described, consisting of subjecting pot clay test pieces of known composition to the corrosive influences of batch or glass and measuring the decrease in area, which seems likely to offer a method for studying the problem of corrosion. The method gave information of the effect on the quality of the glass and also on the tendency of the refractory to form pits. Generally speaking, siliceous clays were found to become corroded more than the aluminous ones. The effect of the structure of the clay on the extent of corrosion is very important. Close grained, aluminous clay specimens resisted the effects of corrosion to the highest degree. The quality of the glass from the point of view of freedom from cord can be judged from an examination of sections prepared by founding the glass in crucibles of the clay in question, pouring the glass so as to form thin slabs, which are then ground and polished. Certain clays gave glass which was singularly free from cord whereas with others the reverse was the case. The quality of the glass was not dependent on the amount of corrosion but rather on the nature of the material passing into solution. It was impossible to remove the strain from the very cordy specimens by annealing. The nature of the white layer which forms on the surface of aluminous clay refractories heated in contact with glass is discussed.

J. H. Partridge, G. F. Adams & J. R. Lait