Elastic Moduli Of Beryllium Versus Temperature: Experimental Data Updating

The evolution of the elastic moduli (Young modulus-E; adiabatic bulk modulus-B(S) and shear modulus-G and Poisson's ratio-nu) in the temperature range T is an element of [300;1000] K or T/T(m) is an element of [0.2;0.65] of isotropic polycrystalline beryllium samples was investigated using an ultrasonic method. The key point is to perform the relevant and consistent analysis of the complete set of elastic data taking account of the specific low values of nu (at ambient and at high temperature). The evolution of the elastic moduli is shown to be governed by the density evolution through the thermal expansion coefficient. Then, the elastic moduli versus temperature are accurately discussed and are at variance with the only known experimental data from 1972 [W. D. Rowland, J. Phys. F: Met. Phys. 2, 231 (1972)]. The analysis is completed by a comparison with computations performed by first-principle calculations [G. Robert et al. (unpublished)]. (C) 2010 American Institute of Physics. [doi:10.1063/1.3455859]