GLASS-CERAMIC FLOTATION

摘要

The invention relates to a method for manufacturing a flat strip of glass as a precursor of glass-ceramic, that comprises the continuous flotation of the molten glass on a molten metal melt in a flotation housing, said glass being poured at the molten state and at a temperature exceeding the devitrification starting temperature on the molten metal upstream from the housing, said glass progressively forming a running strip on said metal melt, the glass cooling speed being of at least 18°C/min between, on the one side, the moment when the glass is at the theoretical temperature of maximum devitrification rate and, on the other end, the following moment when the glass is at the theoretical temperature at which the devitrification crystal growth rate becomes lower than 1 micron per minute. The glass thus floated shows no devitrification.