Formation of dendritic precipitates in the beta phase of Cu-based alloys

The isothermal treatment of the β phase in some Cu-based alloys produces its decomposition by an earlier precipitation of γ phase. During their growth, by means of a diffusion-controlled process, the precipitates show evidences of morphological changes. In the first stages and for a Cu–Zn–Al alloy, the morphology is spherical and cuboidal, but develops more complex shapes such as dendrites, owing to composition fields, interphase overlapping, crystallography characteristics, and relative orientation. In this work, a dendritic γ precipitate characterization is done and morphological theoretical predictions are applied, for Cu–Zn–Al and Cu–Al–Be alloys.