Abstract
Fe-Cr-Al alloy powder was plasma sprayed using a water stabilized plasma gun. The alloy simulated the commercial KANTHAL D. To obtain its composition in a plasma deposit, the initial powder composition must have been somewhat different to cope with the changes due to selective vaporization and selective oxidation during spraying. For the changes at the in-flight stage of spraying, mainly selective Al vaporization is responsible. After particle impact and solidification, i.e. during formation and cooling of a coating, vaporization is interrupted and the composition changes due to oxidation are less significant. During plasma spraying, the alloy exhibits better oxidation resistance than a number of materials. The protective mechanism is virtually the same as in solid Fe-Cr-Al alloys, nevertheless the protective Al₂O₃ layer is liquid under the reaction conditions.

Key words
Fe-Cr-Al alloy powder, plasma spraying, oxidation, vaporization, composition changes

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