Methodological problems in experimental studies and verification of the governing equations of the theory of elasticity for an isotropic body with different moduli in tension and compression

We examine a range of issues related to the methodological and experimental support of a linear elastic model for an isotropic body with different moduli in tension and compression in mechanical tests of solid samples of different origin and structure. The reasons for the difference between tensile and compressive Young's moduli measured in the tests are analyzed. It is shown that using appropriate test techniques and equipment for measuring and recording deformations sustained by a homogeneous uniaxial state makes it possible to obtain statistically insignificant differences in Young's modulus for a number of materials subjected to tensile and compressive forces.