Corrosion mechanisms of materials

The effect of the main factors governing the corrosion rate (CR) on the combustion gas side is described below. Corrosion rates depend on the metal temperature and the gas temperature these are considered to be the main factors determining the deposition rate and the composition of the deposits. As the temperature gradient (AT = gas temperature - metal temperature) is the driving force for condensation and deposition of the vapor components in the gas, the chloride concentration in the deposits is 

50% 1102/50% alloy 625 cermet HVOF coating after 13.800 hours exposure,  

8 Zr02/Alloy 625 on-site 100 kW plasma-jet spray coating for 500°C superheaters. 

9 Change in corrosion weight ioss with moiten phase content between coating test and crucibie test. 

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