Alloys for high-temperature corrosion

Alloys designed to resist high-temperature corrosion are basically oxidation-resistant materials because all forms of attack at elevated temperatures are 

Critical Pitting Temperature of Alloy H-9M in Comparison to Other Alloys 

Cycling temperatures will tend to spall off the surface film, leading to a stepwise oxidation of the alloy. Changes in the environment can have the same effect. 

Although all high-temperature corrosion is considered oxidation, there are other terms that are also encountered, such as oxidation-reduction, sulfidation, fuel ash corrosion, carburization, and nitridation, to name a few. 

Although many of the high-nickel alloys previously discussed can be utilized at elevated temperatures, there are some instances where the materials are not satisfactory. Consequently, other alloys have been developed to overcome these shortcomings. 

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