EVIDENCE FOR THE SEGREGATION OF SULFUR TO NI-ALUMINA INTERFACES

The S enrichment of Ni-sapphire interfaces in the temperature range 50 0-800 degrees C was measured with Auger electron spectroscopy. Atomic force microscopy was used to confirm that S segregated to the interfac e rather than to interface voids or grain boundaries. The effects of a tomic defects such as dislocations on S segregation was not determined . Maximum segregation occurred at 700 degrees C, similar to that to Ni grain boundaries. (C) 1997 Elsevier Science B.V.