Mechanical Properties of CeF3 Single Crystals

The anisotropy of the mechanical characteristics of CeF3 crystals (sp. gr. P (3) over bar c1 ) grown from the melt by the Bridgman technique has been studied for the first time. The variability of Young's modulus, the shear modulus, and the Poisson's ratio has been analyzed and the Vickers microhardness HV of the (0001) and (10 (1) over bar0) crystal planes at room temperature has been determined (2.9 and 2.3 GPa, respectively, under a load of P = 60 g). The {11 (2) over bar0} primary cleavage surfaces (slip planes) and the {10 (1) over bar0} and {0001} secondary cleavage planes for the CeF3 crystals have been established. A correlation between the shape of Vickers indentations and the Young's modulus anisotropy have been observed.