Dezincification of α-Cu-Zn

Cu-25.4 at% Zn samples were dezincified in vacuum at 450, 500, and 800°C, and the changes in composition and pore configuration were followed mainly by scanning electron microscopy. Samples with (100) and (111) surface orientation were used in the experiments. A smaller evaporation rate for (111) with respect to (100) surfaces could be observed. Three stages in the dezincification could be established: a) a homogeneous dezincification without pore formation in the very initial stage; b) the pore formation stage with round pores which could develop into segmented shapes, exposing preferentially (111) close packed planes; and c) the formation of irregular strings of pores, whose collapse leads to grooves at 800°C.