Elastic constants of monocrystal iron from 3 to 500 K

Resonant ultrasound spectroscopy was used to measure the monocrystal elastic constants of iron over a temperature range of 3-500 K. All the moduli behave normally as a function of temperature and are well described by the semiempirical Einstein-oscillator model. Values at 300 K are bulk modulus=166.2 +/- 0.9 GPa; shear constant C-'=(C-11-C-12)/2=48.15 +/- 0.9 GPa; shear constant C-44=115.87 +/- 0.17 GPa. The Poisson ratio (nu(100)) is 0.3679 +/- 0.0005. Representation surfaces of Young's and torsion moduli are presented. The Debye temperature (theta(D)) is 476.3 K as calculated from 3 K measured elastic constants. A thermodynamic Gruneisen parameter gamma(th)=1.65 is calculated. The temperature dependence of the internal friction associated with C-' is very different from that associated with C-44. Possible reasons for this difference are suggested. (c) 2006 American Institute of Physics.