Measuring elastic parameters of transversely isotropic materials by cylindrical indentation

Based on the cylindrical indentation experiments, a novel model for characterizing the elastic mechanical property of transversely isotropic materials has been established. The cylindrical indentation of transversely isotropic materials was theoretically and dimensionally analyzed. Three-dimensional (3D) indentation experiments that encompass the wide range of transversely isotropic material parameters were simulated by finite element. The effect of each parameter (transversely isotropic Young's modulus, EP, longitudinal Young's modulus, EL, longitudinal shear modulus, GL, and loading orientation angle, a) on the normalized indentation modulus was investigated. Then, the dimensionless analytical relationship between indentation moduli and elastic parameters was obtained at three different indentation orientations (a = 0 degrees, 45 degrees, and 90 degrees). Several groups of transversely isotropic materials were selected as input parameters to carry out numerical indentation experiments for the error analysis. The sensitivity of the calculated elastic parameters to the experimental data was analyzed. Simultaneously, the technique was used in the particular case of a Zinc single-crystal material, and the accuracy of these derived formulas was verified. The good agreement shows that the proposed method is reliable and could be applied to characterize the elastic parameters of transversely isotropic materials.