Examination of elemental nonuniformities in laser surface melted ternary copper alloys

The enhanced corrosion resistance of laser melted surfaces is often rationalized from the viewpoint of the homogenizing nature of the rapid quench from the liquid. We utilize Auger spectroscopy to examine elemental nonuniformities in laser surface melted ternary copper alloys (CDA‐614 and CDA‐725). In both systems we find depletion of the highest vapor pressure element from the central area of laser melt stripes, that region which reaches the highest temperature and remains molten for the greatest period of time. Although this near surface depletion is a small effect relative to the homogenization taking place over the orders of 10 and 10 2 µm, it may be a significant effect which should be taken into account when explaining changes in corrosion and oxidation behavior.