Point defect formation in M₂AlC (M = Zr,Cr) MAX phases and their tendency to disorder and amorphize.

ABSTRACT: First principles calculations are performed on Zr₂AlC and Cr₂AlC MAX phases to compare their ability to accommodate point defects under irradiation. Interatomic bonding is stronger in Cr₂AlC than Zr₂AlC but contrary to expectation Zr₂AlC exhibits higher vacancy and antisite pair formation energies. However, interstitials and Frenkel defects are generally more difficult to form in Cr₂AlC. The results are attributed to the mixed covalent/ionic/metallic nature of the bonding. Detailed comparison of all the energies suggests that the preferred defects in Zr₂AlC and Cr₂AlC are the V_Al+Al_i Frenkel and Cr_Al+Al_Cr antisite respectively. Thus the potential response of t

SUBMITTER: Shah SH 

PROVIDER: S-EPMC5574895 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature