The influence of surface preparation method on microstructure of Hf-modified aluminide coatings deposited by CVD method on Rene 80 and MAR M247 nickel superalloys

摘要

In the article the hafnium modified aluminide coatings deposited using chemical vapour deposition (CVD) method were analyzed. The influence of surface treatment (grinding, sandblasting with different pressures) on microstructure of coatings were described. The Rene 80 and MAR M247 nickel superalloys were used as substrate. Thickness of the obtained aluminide coating was in the range 32-45 μm on Rene 80 and 40-45 μm on MAR M247 respectively. The average amount of Al in the additive layer was 22-24 wt% on Rene 80 and about 21 wt % on M-247 base alloy. The total amount of hafnium in coatings did not exceed 2.5 wt % - usually below 0.5 wt %. The conducted research has shown that there is no strong influence of surface preparation methodology on microstructure of aluminide coatings obtained by CVD method..