PChem Seminar – Wyatt Kiff

About the event

Speaker: Wyatt Kiff

Group: Dr. John McCloy

Title: Determining Non-isothermal Nucleation Kinetics Across the Na2Ca2Si3O9 – NaAlSiO4 Join Through Complementary and In-Situ Methods

Abstract:

The crystallization of glass is important both for practical applications, and for understanding glass stability and formability. Traditional investigations include isothermal heat treatments and microscopy, providing reliable nucleation rates. However, recent advancements in instrumentation and analytical techniques motivate the use of non-isothermal thermal analysis to determine crystallization and growth rates of glassy systems. Non-isothermal methods have described model systems such as Na2Ca2Si3O9 (mineral combeite) but remain under-investigated in behaviorally complicated and off-stoichiometric systems. Though, thermal analysis may elegantly probe the crystallization kinetics, these techniques are intricate and require additional context of the glassy system. Use of in-situ methods can provide complementary information, allowing for comprehensive insight. Here we study the compositional join between homogenously nucleating Na2Ca2Si3O9, to the complex nucleating tectosilicate NaAlSiO4 (mineral nepheline/carnegieite). Of these systems, the crystallization and nucleation kinetics are being investigated through complementary calorimetric non-isothermal analysis (DTA/DSC) and in-situ structural analysis techniques. The complementary methods are applied to the compositional join, determining the effective crystallization behavior.