The deformation behaviour of Au nanowires subjected to uniaxial tension at high strain-rate under different temperatures is studied by molecular dynamics simulation along [001], [011], and [111] elongation directions, respectively. The stress distributions and the radial distribution functions of the structure of the nanowires are evaluated and discussed. It is seen that the stress-strain curves are quite different from those of the bulk material. Moreover, the microstructures of nanowires are transformed first from FCC to face-centred-orthorhombic-like crystalline, and then changed to the amorphous state. The first neighbouring distance in the radial distribution functions along the [001] direction is clearly split into two peaks. It appears that the ductility of the nanowires at high strain-rate is higher than the corresponding macroscopic cases. The magnitudes of Young's modulus and the maximum strength along different crystalline directions are evaluated and compared with each other. They tend to decrease as the temperature increases. It may be predicted from our simulations that the conductance at high strain-rate deformation may be a continuous function of elongation due to the smooth reduction of area.

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The interconversions between relaxation moduli and creep compliances, including stretch, shear, bulk parts, and the time-dependent Poisson's ratio, are derived by using the relaxation-creep duality representation. The relaxation-creep duality representation for the viscoelastic functions introduced in this paper is composed of an exponential function that characterizes the relaxation behavior and a complementary one that characterizes the creep behavior. All viscoelastic functions can be represented as the same form. The new sets of coefficients, called the modulating constants, between viscoelastic functions obey the elastic-like interconversions, and do not involve the characteristic times. The relationships of characteristic times between those functions are also derived. These interconversion formulas can then be calculated easily. Three literatures are referenced to calculate the consistency of the viscoelastic functions via the new interconversions introduced in this work. The Young's relaxation modulus in one literature is not consistent to the shear one in another literature. By assuming a constant bulk modulus, the modified Young's relaxation modulus and time-dependent Poisson's ratio that was derived by the new interconversions can meet the measured curves and can be consistent to the shear creep compliance in the literatures. The fitted data from experiments can then be checked via the new mathematical interconversions for the consistency.

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The interconversion relations for viscoelastic functions are derived with the consideration of the time-dependent bulk modulus, K(t), for both traditional and fractional Prony series representations of viscoelasticity. The application of these relations is to replace the fitting parameters of Young’s relaxation modulus, E(t), by the unknown parameters of K(t) and the known parameters of the shear relaxation modulus, G(t), and to fit the E(t) to the experimental data for obtaining the parameters of K(t). The fitting results show that only two experiments for measuring the viscoelastic functions of an isotropic material are not enough to determine the other viscoelastic functions. However, if we consider the relaxation rates of K(t) and G(t), we may conclude that the constant bulk modulus is a more reasonable assumption, and the corresponding Poisson’s ratio, ν(t), is a monotonic-increasing function.

 The inferred b-value for acoustic emission apparent amplitude is equal to that at source irrespective of the form of attenuation law.  The finite size of the sample leads to a finite range of applicability of the Gutenberg-Richter law.  A new method is used to determine the finite range, and its application confirms b depends on material heterogeneity and stress.

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