Note on the Determination of the Devitrification Temperatures of Glasses

JSGT 1940 V24 T101-T108

 A modified gradient method of devitrification temperature determination is described and results from it are compared with those previously obtained by workers employing the classical quenching method. The method is shown to be reliable and capable of giving information at the same time on the rate of crystal growth at temperatures throughout the devitrification range. Examples of errors due to non-establishment of equilibrium, and surface devitrification brought about by volatilisation of one or more of the glass constituents are described.

Eric Preston, Ph.D., D.Sc., F.I.C., F.Inst.P.