The present investigation is focused on the influence of the nanocrystalline structure of pure iron metal on the ultrasonic properties in the temperature range 100 - 300 K. The ultrasonic attenuation due to phonon- ph...The present investigation is focused on the influence of the nanocrystalline structure of pure iron metal on the ultrasonic properties in the temperature range 100 - 300 K. The ultrasonic attenuation due to phonon- phonon interaction and thermoelastic relaxation phenomena has been evaluated for longitudinal and shear waves along , and crystallographic directions. The second-and third-order elastic constants, ultrasonic velocities, thermal relaxation, anisotropy and acoustic coupling constants were also com- puted for the evaluation of ultrasonic attenuation in this temperature scale. The direction is most ap- propriate to study longitudinal sound waves, while , direction are best to propagate shear waves due to lowest values of attenuation in these directions. Other physical properties correlated with obtained results have been discussed.展开更多
文摘The present investigation is focused on the influence of the nanocrystalline structure of pure iron metal on the ultrasonic properties in the temperature range 100 - 300 K. The ultrasonic attenuation due to phonon- phonon interaction and thermoelastic relaxation phenomena has been evaluated for longitudinal and shear waves along , and crystallographic directions. The second-and third-order elastic constants, ultrasonic velocities, thermal relaxation, anisotropy and acoustic coupling constants were also com- puted for the evaluation of ultrasonic attenuation in this temperature scale. The direction is most ap- propriate to study longitudinal sound waves, while , direction are best to propagate shear waves due to lowest values of attenuation in these directions. Other physical properties correlated with obtained results have been discussed.
