Third‐Order Elastic Constants of Ge, MgO, and Fused SiO2

The third‐order elastic constants of germanium, magnesium oxide, and fused silica have been measured using the pulse superposition method for determining the ultrasonic velocity as a function of both uniaxial and hydrostatic pressure. From these measurements all six third‐order elastic constants were calculated by using the equations of Thurston and Brugger for MgO and Ge, and the three independent isotropic third‐order constants were calculated for fused SiO2.The results for Ge are in good agreement with the most recent data of McSkimin and Andreatch. The results for MgO agree in part quite well with theoretical data calculated from a Born‐Mayer potential. Drastic failure of the three Cauchy relations indicates the presence of many body forces. For fused silica, the remaining Cauchy relation is, as may be expected, not well fulfilled.

[1]  T. B. Bateman,et al.  Third‐Order Elastic Moduli of Germanium , 1961 .

[2]  H. J. Mcskimin,et al.  Pulse Superposition Method for Measuring Ultrasonic Wave Velocities in Solids , 1961 .

[3]  D. Chung,et al.  Relation of Single‐Crystal Elastic Constants to Polycrystalline Isotropic Elastic Moduli of MgO , 1963 .

[4]  T. B. Bateman,et al.  Ultrasonic‐Wave Propagation in Pure Silicon and Germanium , 1964 .

[5]  H. J. Mcskimin,et al.  Elastic Moduli of Silicon vs Hydrostatic Pressure at 25.0°C and − 195.8°C , 1964 .

[6]  R. Roy,et al.  Effects of High Pressure on Glass: a Possible Piezometer for the 100-Kilobar Region , 1961, Nature.

[7]  R. N. Thurston,et al.  Third-Order Elastic Constants and the Velocity of Small Amplitude Elastic Waves in Homogeneously Stressed Media , 1964 .

[8]  M. A. Durand.  The Temperature Variation of the Elastic Moduli of NaCl, KCl and MgO , 1936 .

[9]  Percy Williams Bridgman,et al.  The physics of high pressure , 1931 .

[10]  G. L. Pearson,et al.  Deformation and fracture of small silicon crystals , 1957 .

[11]  M. Born,et al.  Dynamical Theory of Crystal Lattices , 1954 .

[12]  D. S. Hughes,et al.  Second-Order Elastic Deformation of Solids , 1953 .

[13]  F. Birch.  Finite Elastic Strain of Cubic Crystals , 1947 .

[14]  H. J. Mcskimin,et al.  Elastic Moduli of Germanium Versus Hydrostatic Pressure at 25.0°C and −195.8°C , 1963 .

[15]  H. J. Mcskimin,et al.  Measurement of Third‐Order Moduli of Silicon and Germanium , 1964 .

[16]  H. J. Mcskimin,et al.  Analysis of the Pulse Superposition Method for Measuring Ultrasonic Wave Velocities as a Function of Temperature and Pressure , 1962 .