Studies on Cr-Mo binary alloys II. Cross-over in surface segregation for chromium-rich alloys

The equilibrium segregation behaviour of an 83.4 at% Cr-Mo alloy has been studied by Auger electron spectroscopy. The high chemical affinity of Cr, particularly for nitrogen, and its high vapour pressure made cleaning of this alloy difficult. Several cleaning techniques were tried, but the only successful procedure was a tedious sequence of 530 sputter-anneal cycles, which we have optimised by microcomputer control. The changes in the Auger …