Experimental evidence of zonal dislocations in the Ti2AlC MAX phase

• Published in: Materials characterization 2023-06, Vol.200, p.112882, Article 112882
• Main Authors: Mussi, Alexandre, Henzelmeier, Adrien, Weidner, Timmo, Novelli, Marc, Wenbo, Yu, Cuvilly, Fabien, Grosdidier, Thierry, Guitton, Antoine
• Format: Article
• Language: English
• Subjects: Condensed Matter; Dislocations; Engineering Sciences; Materials; Materials and structures in mechanics; MAX phases; Mechanics; Physics; Severe plastic deformation; Surface mechanical attrition treatment; Transmission electron microscopy
• ISSN: 1044-5803; 1873-4189
• DOI: 10.1016/j.matchar.2023.112882

The dislocation configurations of a Ti2AlC-MAX phase deformed under severe plastic deformation by surface mechanical attrition treatment have been analyzed by transmission electron microscopy. Results show that the microstructure of the deformed Ti2AlC sample is composed of numerous 〈a〉-dislocations, which interact with each other notably with dipolar configurations. In addition, we report here 〈a〉-dislocation dissociations in the basal plane with a dissociation distance of approximately 20 nm, following the reaction 1321¯1¯0⇔1311¯00+13101¯0. Finally, evidence of zonal dislocations is reported. These original results are discussed in the context of the fundamental deformation mechanisms of nanolayered ternary alloys. [Display omitted] •TEM analyses of a severe plastically deformed Ti2AlC MAX phase are reported.•Dipoles and dissociations of dislocations are characterized.•Zonal dislocations are characterized for the first time in MAX phases.•Such zonal dislocations were predicted by simulation in MAX phases.