TEM observation of oxidation of CuZnAlMnNi shape memory alloy

The atmospheric oxidation of a quenched CuZnAlMnNi alloy after ion-polishin g was examined by transmission electron microscopy (TEM). It was found that a lot of oxide grains with various sizes yield homogeneously on the surfac e of the alloy after exposure at room temperature for 90 d. The grains main ly form along the planes of stacking fault, meanwhile, they can also be obs erved at the stacking fault tetrahedrals or around the dislocation lines. T he formation of the oxides gives rise to the reduction of the stacking faul ts, and even complete disappearance in some zones, which is partly responsi ble for the decrement of shape memory effect (SME) of the alloy quenched du ring long-term holding at room temperature.