Effect of Post-Annealing Treatment on Mechanical Properties of ZnO Thin Films

The present work was focused to study nanomechanical properties of ZnO thin films deposited on different substrates (Corning Glass and Fused Quartz) using DC-sputtering. The crystallinity and microstructure are correlated with process conditions and post annealing treatment in NH3 environment, which in turn affects the mechanical performance. The structural growth accompanied a change in crystalline nature and microstructure as the substrate is altered from corning glass substrate to fused quartz at similar synthesis conditions. The post deposition annealed ZnO thin films demonstrated agglomerated particles with no clear grain boundaries having nano-cracks present in the morphology, which is attributed as NH3 effect on microstructure. The mechanical properties such as hardness (6.89-7.76 GPa), Young’s modulus (94.9-124.6 GPa), and coefficient of friction ̴ (1.0-3.0) of ZnO thin films were measured using three sided pyramidal Berkovich nanoindentation. Load-unload segment of indentation curve of thin films which is measured at continuous loading revealed no event of discontinuity (≥ 2 nm) during loading/unloading, indicating no fracture or delamination during indentation. The critical load of ZnO thin films failure was analysed using scratch testing ramp loading and the value of critical load was found around ̴535.6 µN to ̴668.4 µN

Experimental investigation and Monte Carlo Simulation of glass transition in polymer nanocomposites

Journal of Metastable and Nanocrystalline Materials23339-34

Thermodynamics of surface compositional segregation in Ni-Co nanoparticles

10.1016/S0921-5107(02)00221-0Materials Science and Engineering B: Solid-State Materials for Advanced Technology952116-123MSBT

Monte Carlo simulation of surface segregation in nanoparticles

Journal of Metastable and Nanocrystalline Materials23203-20

Thermodynamic modeling of surface segregation in Au-Ti nanoparticles

Journal of Metastable and Nanocrystalline Materials23259-26

Activities of Al in the Al-Ga-In-Sb system in the temperature range of 1073-1273 K

The multicomponent alloy systems containing group III and V elements are particularly important for their electrical and optoelectronic applications. An accurate knowledge of their thermodynamic properties provides the essential tool in the determination of the phase equilibria which will be useful in processing the semiconducting materials. It may be mentioned that Zbitnew et al. [1] studied the quaternary system using x-ray Debye Scherrer powder photographic technique and x-ray fluorescence for the lattice parameter measurements and the chemical analysis respectively. They have shown that there is complete miscibility between Al-Sb, Ga-Sb, and InSb compounds which results in the formation of isomorphous pseudoternary solid solutions. Thermodynamic modelling of the quaternary system has been carried out by Sharma et al. [2] using a quasi sub-sub regular solution model based on the available information of the constituent binary and ternary properties. In the absence of any activity data, the present investigation measures the activities of Al in the liquid Al-Ga-In-Sb system using a concentration cell of the type

Thermodynamics and phase equilibria in the Al-In-Sb system

As part of a program for determination of the thermodynamic properties of the group III and V alloys and assessment of the phase equilibria, the activities of aluminum in the liquid Al-In-Sb system have been measured using a concentration cell of the type Al (1)/NaCl+KCl+3 mole pct $AlCl_3Al-In-Sb$ (1) The measurements are carried out along the constant compositional paths of $x_{Sb}=0.1$ and 0.2 over a temperature range of 1073 to 1273 K. The measured activity data in the system exhibit positive deviations from ideality. The deviations increase progressively with the In content of the alloys for a constant compositional path of Sb. The magnitude of the aAl as a function of In is found to decrease significantly with the increase in the Sb content of the alloys. The behavior is consistent with the existence of the liquid-liquid immiscibility in the syste

Thermodynamics and phase equilibria in the A1-Ga system

As part of a programme to re-establish the thermodynamic properties of III V alloys and reassessment of the phase equilibria, the activities of aluminium in liquid A1-Ga alloys have been determined using a concentration cell of the type $Al(1)\vert NaCl + KCl + 3mol.$% $AlCl_3\vert Al_xGa_{1-x}$ The measurements were carried out over a wide temperature range from 925 to 1275 K and a compositional range $x_{Ga}= 0.1 -0.9$. The activities of A1 in the AI-Ga alloys exhibit positive deviation from ideality. The deviation is found to decrease progressively with increase in temperature and A1 content of the alloys. The phase equilibria in the system are evaluated using a five-parameter excess free energy function using the experimental data. The calculated solidus and liquidus boundaries of the system based on the present investigation are compared with those determined by the earlier evaluations and experimentally determined values available in the literature

Applicability of a dilute quaternary model in interpreting the thermodynamic properties of the Fe-Ni-Ta-N system

Interaction parameter formalism is considered to be important for representation of the excess thermo- dynamic properties of multi-component systems.- Wagner (1) proposed an interaction parameter for- malism to dilute multi- component systems through a Maclaurin infinite series expansion for the partial excess free ene:rgy. Several researchers (2-10) have extended this approach to concentrated solution. Since the data for higher order parameters are not readily available, the activity coefficients of solutes at infinite dilutions have so far been used in calculating the excess properties of solutions. It has cently been shown that truncation of the Maclaurin infinite series removes exactness of the expressions for the activity coefficients of solutes in multi-component systems (3,6,7). It may be mentioned that some of the authors have suggested (a) special relations between interaction parameters and (b) intro- duction of a constant compositional path toward the solution of the problem. To overcome these con- straints, the present authors (10) have deduced the partial functions of the ternary system from the Maclaurin infincite series that is expressed in terms of the integral excess function of the system. The infinite series is subjected to appropriate boundary conditions and each of the terms of the series correlated to the corresponding interaction coefficients of the solutes of the system. In the present article, the same method as adopted in our earlier article (10) has been used for deducing the partials the Quatenary System. The derivation of $ln\gamma_1$ $ln\gamma_2,$ $ln\gamma_3$ and $ln\gamma_4$, of the quaternary system involves extensive sumrnation of various infinite series pertaining to first order and quaternary parameters order to preserve thermodynamic consistency. Although the derivation and consistency of the partials are described elsewhere (12), a brief outline of the latter with an emphasis of their applicability to experimental data (11) of the Fe-Ni-Ta-N system in the temperature range of 1796- 983K presented