Elastic properties of Ta4AlC3 studied by first-principles calculations

Elastic properties of Ta4AlC3 were studied by first-principles calculations. The five independent elastic constants were derived yielding c 11 = 437 GPa , c 12 = 158 GPa , c 13 = 197 GPa , c 33 = 416 GPa , c 44 = 165 GPa . The bulk modulus B , Young’s modulus E , shear modulus G , and Poisson’s ratio v were determined to be 266 GPa, 362 GPa, 142 GPa, and 0.27, respectively. Ta4AlC3 is elastically stable with a Ti4AlN3-like structure. Ta4AlC3 exhibits largely isotropic properties in compression and is slightly anisotropic in shear. The in-plane elastic anisotropy in a – c plane of Ta4AlC3 was also revealed.