Crystallization Measurements Using DTA Methods: Applications to Zerodur

Differential thermal analysis (DTA) experiments described herein apply two methodologies by which to estimate absolute nucleation rates and/or temperature dependencies using a low‐expansion, commercially relevant, multicomponent glass‐ceramic as a test material. In particular, the Marotta and the Ray et al. methods were applied to Zerodur® and both provided valuable insight into a relatively complicated crystallization process. Previous nucleation and crystal growth rate data were used in a comparative manner. Although the Marotta method accurately predicted the maximum nucleation temperature, the nature of the technique precluded an estimation of absolute nucleation rates. The Ray et al. technique provided reasonable nucleation rates, but failed to provide useful estimates of the number of quenched‐in nuclei, in part because of a substantial “blank” contribution coming from additional, unwanted nucleation during heating and cooling stages of the DTA technique.