Hot Corrosion of Diesel Engine Exhaust Valves

The purpose of this paper is to show that although “hot corrosion” (which is, in fact, a sulfidation-accelerated oxidation phenomenon) is more prevalent in gas turbine applications, diesel engines are not immune to this under certain conditions. Evidence of this type of corrosion in the case of some iron-base and nickel-base exhaust valves is presented to illustrate the point. The successive stages of the corrosion process are discussed, and the beneficial effects of some alloying elements in affording protection against hot corrosion are pointed out.