STRUCTURE-HARDNESS RELATION FOR HIGH-TEMPERATURE SO2-DEALKALIZED FLOAT GLASS

Changes in the surface mechanical properties of float glass that had b een heat treated in atmospheres containing SO2 gas were measured. An a nalysis combining dynamic microhardness and structure investigations i ndicates that a relation exists between the hardness and surface struc ture. This relation is used in establishing an understanding of the mi crohardness variations and the corresponding surface mechanical proper ties. The treatment parameters, temperature, time and treatment atmosp here conditions, are shown to have an effect on these properties. Thei r extent is suggested to depend on the formation of a thermal expansio n coefficient difference between a dealkalized surface and the interio r dealkalization properties and structure alterations. The changes in the mechanical properties are described which connect these effects. T he structure-hardness relation of the air side differs from the tin si de of float glass. (C) 1997 Elsevier Science B.V.