The effect of corrosive coating on the creep deformation and rupture p
roperties of 2.25Cr-1Mo ferritic steel has been studied in the tempera
ture range of 550-700-degrees-C. The corrosive coating used, was a mix
ture of 40% potassium sulphate and 60% sodium chloride which has been
found to have the lowest melting point of 507-degrees-C. Coating incre
ases the creep rate and reduces the rupture life. Formation of liquid
phase accelerated the corrosion attack and reduced the creep strength.