Investigation of the disorder– order phase transition series during the cooling process of the 12-carat au cu alloy by in-situ temperature xrd and mechanical spectroscopy

Abstract

This work investigates the disorder order phase transition occurring during the cooling of a 12-carat Au–Cu alloy. The alloy was characterized using in-situ temperature X-ray diffraction (XRD) and mechanical spectroscopy. The results showed that the alloy transforms from a disordered A1 phase at high temperature to an ordered AuCu₃ phase during cooling. The onset of the transformation was detected around 633 K, while the ordered phase became predominant around 525 K. The appearance of superlattice reflections and the observation of a Zener relaxation peak confirmed the atomic ordering process. These findings provide a better understanding of the relationship between phase transformations, atomic ordering,and mechanical behavior in Au–Cu alloys