Mechanical and thermal properties of single crystals of ZrB₂

Coefficients of thermal expansion (CTE), elastic constants and plastic deformation behaviors of single crystals of ZrB₂, which possesses a hexagonal layered structure where pure Zr and pure B atomic planes stack alternatively along the c-axis, have been investigated in wide temperature ranges. While the observed elastic constants indicate highly anisotropic nature of atomic bonding being consistent with the layered structure, the observed CTE values are rather isotropic. Two operative slip systems, (0001)〈112̄0〉 and on {11̄00}〈112̄3〉, are identified in compression tests. The observed plastic behaviors are discussed in the light of the deduced anisotropy in atomic bonding.