Spinodal decomposition and martensitic transformation in Cu-Al-Mn shape memory alloy

VELAZQUEZ, DIEGO EZEQUIEL; ROMERO, RICARDO

JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY

SPRINGER

Lugar: Berlin; Año: 2017 vol. 130 p. 2007 - 2013

1388-6150

Isothermal treatments at 413 K were performed in Cu-Al-Mn shape memory alloy samples, to study their effects on the martensitic transformation. This thermal treatment, within the miscibility gap, produces spinodal decomposition. After each aging thermal treatment, martensitic transformation was monitored using Differential Scanning Calorimetry (DSC). Spinodal decomposition significantly changes the characteristics of the martensitic transition, reducing the transformed volume and modifying the critical temperatures. Further, a narrowing in transformation hysteresis loop is observed when the volume fraction of the spinodal precipitates increases. Effects of thermal cycling through the martensitic transformation were studied in aged alloy samples. It was found that the cycling produces critical temperatures changes, a transformed volume fraction increase, and a widen hysteresis loop. The observed results were discussed considering the interaction between spinodal precipitates and martensitic plates.