Application of differential thermal analysis to solid-solid transitions in phase diagram determination

Abstract

The differential thermal analysis (DTA) procedure is presented for the determination of equilibrium phase diagrams. The equilibrium solid-solid phase transition temperatures, which are needed in the construction of phase diagrams, cannot be obtained directly from the DTA data due to the superheating or undercooling during the actual DTA operation. Methods to extrapolate the equilibrium onset temperature for the solid-solid phase transitions from the DTA data are evaluated. Several practical problems in the DTA experiments and analysis are addressed.