Fundamental Influence of C on Cohesion of Pd/TiAl Interfaces

Abstract

First-principles calculations reveal that for Pd/TiAl interfaces the doping of C atoms at the surface centers of Pd interface layers could both increase the bond strength by a factor of 2 and decrease the interface energy by a factor of 3, suggesting that C would be a good doping candidate of increasing the lifetime of Pd/TiAl membranes. Calculations also show that although the addition of C atoms decreases the interface bond strength of Pd–Al and Pd–Ti bonds, the extra interface Ti–C and Al–C bonds are strong enough to induce the strengthening effect of the C doping.