Kazuhide Ishii

Oxidation resistance of rapidly solidified FeCrAl ribbons at high temperature

Abstract To apply the rapid solidification method to the production of FeCrAl alloy foils for use in the substrate of catalytic converters in automobile exhaust systems, the oxidation behavior of FeCrAlSiLa (Cr, 20–29; Al, 5–10; Si, 0–4; La, 0.03–0.2 (mass%)) alloy ribbons produced by a single-roller method was studied. Rapidly solidified ribbons had better oxidation resistance than that for conventionally rolled foils with a smaller La addition. Increasing the Cr or Al content improved the oxidation resistance of the ribbons, while increasing the Si content did not cause any improvement.

Development of Oxidation Resistant Fe-20Cr-5Al Foil for Catalytic Converter Use

To develop an Fe-Cr-Al alloy foil for catalytic converter use, the effect of the addition of rare earth metals on the oxidation resistance of these foils was studied. It was found that adding La remarkably improves oxidation resistance, while adding Ce reduces it. The workability of Fe-Cr-Al alloys was also investigated, it was clarified that adding 0.06% Ti and reducing the contents of C and N improves workability sufficiently for production by conventional processes. Based on these results, an Fe-20Cr-5Al-0.08La-0.06Ti alloy, which has excellent oxidation resistance, has been developed. In tests, catalytic converters with metal supports made of this foil showed higher performance than those with ceramic supports.