Neutron diffraction analysis of the β decomposition process in a texture free Cu–Al–Ni shape memory alloy

Abstract

The atomic order of the metastable β phase influences on the characteristics of the martensitic transformation in Cu–Al–Ni shape memory alloys. On the other hand, the pro-eutectoid γ 1 precipitation and the eutectoid decomposition produce deleterious effects in the martensitic transformation. In this work, the Rietveld analysis performed on neutron diffraction spectra allows to determine the order, the volume fraction of the different precipitated phases and their evolution during heating in a Cu–14.37Al–4.2Ni (wt%) shape memory alloy.