The use of pure Cu and several Cu-alloy coatings as diffusion barriers to prevent nitridation of Cr has been investigated. In order to determine the suitability of these alloys for use as coatings, it was first necessary to establish the diffusion conditions of these alloys with Cr. The diffusion couples were obtained by dipping a Cr rod into either liquid Cu or various copper alloys. After the heat treatments at 1025-1375K, the specimens were examined metallographically and the interpenetration of Cr and Cu was determined using electron probe microanalysis. Pure Cu and Cu-Pd alloy displayed the least interdiffusion.
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