イオンプレーティングと酸化拡散処理による溶融炭酸塩型燃料電池セパレータ用耐食コーティングの開発

抄録

In order to improve the corrosion resistance of MCFC separator, a new coating was made by combination of ion plating and heat treatment. The corrosion resistance of coating was investigated by electrochemical corrosion tests in a molten carbonate and MCFC single cell tests. The composition of coating was analyzed by means of EPMA and XRD. The characteristics required for the wet seal area of separator such as the flatness of surface were discussed.
The results obtained are as follows:
(1) Through the plating of Al layer on stainless steel and the heat treatment under a particular condition, the multi-layer coating having aluminum oxide phase at the outer side and Al-Cr-Ni diffusion alloy phase at the inner side is obtained.
(2) The morphology of the coating film is affected by the thickness of Al layer plated on stainless steel.
(3) Corrosion resistance in a molten carbonate environment is dependent on the composition of the oxide layer.