On the Faceted and Inclined Twin Boundary of Titanium Carbide Derived from Nanolaminated Ti3AlC2

Abstract

Due to its high twin boundary energy, the absence of Σ3{112} in covalently bonded TiC has been theoretically adjudged. Here, we report the observation of TiC twin boundaries that consist of Σ3{112} and Σ3{111} steps in a faceted and inclined manner. The twin interface in the transition region is not flat, wherein periodic contrasts resulting from overlapped twins were identified. Based on the microstructural analyses, a formation mechanism for the energy‐expensive Σ3{112} and inclined twin boundaries is elaborated.