Corrosion Performance of Austenitic Alloys in Automobile Exhaust Environments

The performance of several austenitic alloys ranging from low alloy content stainless steels to nickel-base alloys has been evaluated at temperatures from 704–1093°C (1300–2000°F) in cyclic air + 10 percent water vapor and from 704–982°C (1300–1800°F) in gasoline engine exhaust. The gasoline engine exhaust was found to be the more aggresive of the two test environments. A general trend of increasing performance with increasing nickel content was observed. At the highest test temperatures in both tests, the nickel-base alloys clearly displayed superior performance.