3 research outputs found
Pressure Dependent Elastic, Mechanical and Ultrasonic Properties of ZnO Nanotube
No full text115-123ZnO Nanotube with an hcp structure, has been investigated for the transmission of acoustic wave in the 0 to 10 GPA
operating pressure. For this, the Lennard-Jones interaction potential methodology has been utilizing to estimate the
advanced order elastic coefficients (SOECs and TOECs). This model is used to calculate the 2nd and 3rd order elastic
parameters for ZnO Nanotube. Applying SOECs, the additional elastic moduli for ZnO nanotubes, for example the bulk
modulus (B), Young's modulus (Y), as well as shear modulus (G), have been computed. Later, applying SOECs as well as
zincoxide density under the same pressure range, three orientation dependent acoustic velocities, comprising Debye average
velocities, have been studied. Basic thermal characteristics such as specific heat at constant volume (CV), thermal
conductivity k (min) associated with lattice, thermal energy density (E0), thermal relaxation time ( as well as acoustic
coupling coefficients (DL, DS) of ZnO Nanotube have been also calculated at same pressure range. Determining the acoustic
attenuation parameters using the method is also successful, arises due to the interaction of phonons, hardness as well as
melting temperature under various pressure in this research work
Дослідження впливу температури на ультразвукові, механічні та теплові властивості нанодроту срібла
No full textThe present paper reports the elastic, mechanical and thermophysical properties of silver nanowire (Ag NW) using ultrasonic techniques at temperature dependent. Higher order elastic constants are calculated using Coulomb and Born-Mayer potential up to second nearest neighbour. To compute mechanical parameters such as young modulus, bulk modulus, shear modulus tetragonal modulus, Poisson\u27s ratio, fracture to toughness ratio and Zener anisotropy factor for finding imminent performance of the single silver nanowire at temperature dependent using second order elastic constants. The Ag NW is found to be brittle in nature at room temperature. Finally, we have evaluated the ultrasonic velocities, ultrasonic attenuation due to phonon–phonon interaction and thermoelastic relaxation for longitudinal wave and shear waves along <100>, <110> and <111> crystallographic directions in the temperature range 100-300K of silver nanowire using the higher order elastic constants. The attained results are discussed in correlation with available outcomes on these properties for the silver nanowire.У роботі досліджено температурні залежності пружних, механічних та теплофізичних властивостей срібного нанодроту (Ag NW) на основі ультразвукових методів. Пружні константи вищого порядку розраховуються із використанням потенціалу Кулона та Борна-Майєра до другого найближчого сусіда. Для обчислення механічних параметрів, таких як модуль Юнга, модуль об’ємної пружності, тетрагональний модуль зсуву, коефіцієнт Пуассона, відношення руйнування до в’язкості та коефіцієнт анізотропії Зенера, із використанням пружних констант другого порядку, знайдено потрібні умови отримання срібного нанодроту з температурою. Нанодротини Ag при кімнатній температурі є крихкими. Оцінено ультразвукові швидкості, ультразвукові згасання через фонон-фононну взаємодію та термопружну релаксацію нанодротин срібла з використанням пружних констант вищого порядку для поздовжньої хвилі та зсувних хвиль уздовж кристалографічних напрямків <100>, <110> і <111> в діапазоні температур 100 - 300 К. Отримані результати обговорюються у порівнянні із існуючими результатами щодо таких властивостей нанодротин срібла
Pressure Dependent Elastic, Mechanical and Ultrasonic Properties of ZnO Nanotube
Get PDFThe impact of pressure on the elastic and acoustic characteristics of the ZnO nanotube are analyzed using the L-J potential approach. This model is applied to evaluate the 2nd and 3rd order elastic parameters (SOECs and TOECs) for ZnO nanotube. Here in this work, the elastic constants are studied with pressure and it is noticed that the elastic moduli of ZnO nanotube increases monotonically as pressure is increases. We also reports that, the hexagonal ZnO nanotube is mechanically stable with pressures according to Born's elastic stability criteria in the present work. The Voigt–Reuss–Hill method are used to compute elastic parameters such as Young's modulus, bulk modulus, shear modulus and Poisson's ratio under different pressure in the present work. The hardness, thermal conductivity, anisotropy constants, ultrasonic velocity and melting point of ZnO nanotube is evaluated using estimated SOECs in the present work. The second order coefficients are being a tool for calculating acoustic velocities along the z-axis for the operating pressure that has been specified. The computation is also satisfactory in estimating the ultrasonic attenuation, Debye temperature and thermal conductivity k (min) under various pressures (0-10GPa) in this research work
