Superheated Water - Corrosion

Corrosion

Superheated water can be more corrosive than water at ordinary temperatures, and at temperatures above 300 °C special corrosion resistant alloys may be required, depending on other dissolved components dissolved. Continuous use of carbon steel pipes for 20 years at 282 °C has been reported without significant corrosion, and stainless steel cells showed only slight deterioration after 40-50 uses at temperatures up to 350 °C. The degree of corrosion that can be tolerated depends on the use, and even corrosion resistant alloys can fail eventually. Corrosion of an Inconel U-tube in a heat exchanger was blamed for an accident at a nuclear power station. Therefore, for occasional or experimental use, ordinary grades of stainless steel are probably adequate with continuous monitoring, but for critical applications and difficult to service parts, extra care needs to be taken in materials selection.