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The requirements of low cost and high-temperature corrosion resistance for bipolar interconnect plates in solid oxide fuel cell stacks have directed attention to the use of metal plates with oxidation resistant coatings. We have investigated the performance of steel plates with homogenous coatings of CrAlN. The coatings were deposited using RF magnetron sputtering, with Ar as a sputtering gas and N gas added during the growth process. The Cr/Al composition ratio in the coatings was varied in a combinatorial approach. The coatings were subsequently annealed in air for up to 25 h at 800 °C. The composition of the coated plates and the rate of oxidation were characterized using Rutherford backscattering (RBS) and non-Rutherford backscattering analysis. From our results, we conclude that Al rich coatings are more susceptible to oxidation than Cr rich coatings and Cr/Al ratio of 0.9 offers the best resistant to oxidation.