Oxidation and preferential sputteriing of a Cu50Zr50 alloy

The oxidation of a Cu50Zr50 shape memory alloy in air at room temperature w as investigated. Both polished surfaces and surfaces subjected to Ar ion bo mbardment were exposed to air for different time intervals and studied by X -ray photoelectron spectroscopy. A ZrO2 layer with some metallic Cu was det ected on the surface for oxidation times up to 1 h. Prolonged air exposure of polished samples led to oxidation of Cu and a decrease of the relative a mount of ZrO2 on the surface. Preferential sputtering of the alloy by 3 keV Ar ions was also studied and surface enrichment of Zr was observed at stea dy-state conditions. (C) 1999 Elsevier Science B.V. All rights reserved.