The effect of aluminide coating on the creep life of Rene 80 nickel base superalloy

In this paper, the creep strength of Rene 80 superalloy in both uncoated and coated states is studied experimentally. The operation temperature range of this superalloy is 760–982 °C, in order to increase its resistance to surface degradation factors such as oxidation, hot corrosion and erosion at high temperatures, a coating is applied on it and its use without coating is not recommended. In this paper, diffiosion aluminide coatings were applied to this superalloy by two separate methods of pack cemantation and slurry under the brand names of Codep B and IP1041, respectively, and the effect of these coatings on the creep life of this superalloy at 982 °C and metallography is examined by SEM was investigated. For this purpose, samples according to ASTM-E8 standard were produced and after coating along with uncoated samples were subjected to creep test according to ASTM-E139 standard. Control parameters including temperature, stress and service life of uncoated samples are evaluated according to C50TF28 standard. Uncoated creep samples lost their strength after an average of 33 hours and rupture occured. Codep-B coated samples lost their strength after on average of 45 hours and slurry-coated samples lost their strength after on average of 51 hours. The results showed that the coatings increased the creep life of the coated samples compared to the uncoated samples by at least 12 hours.