Study of c2 precipitation in Cu–Al–Be shape memory alloys

Thermal aging between 250 and 500 C of ordered b phase in a polycrystalline Cu–Al–Be shape memory alloy were performed, and the formation of phase c2 was studied with optical and transmission electron microscopies and XRD techniques. The growth of c2 phase shows a polynomial behavior, and Avrami curves as well as a Time–Temperature–Transformation diagram were constructed from these results. In addition, the formation of stable c2 precipitates was studied in aged Cu–Al–Be ribbons. The presence of a regions surrounding c2 precipitates for longer aging times at higher temperatures was observed, giving a consistent precipitation scheme