A new method for automated reconstruction of pre-transformation microstructures

A new method, referred to as the cluster method, is proposed and tested for the reconstruction of pre-transformation microstructure in Ti-6Al-4V alloy. The cluster method begins by constructing clusters of daughter grains (room-temperature hcp -phase) that have a high probability of being transformed from the same parent grain (high-temperature bcc -phase). These clusters are then grown, and back-transformed to the parent grain orientations using the summation of mutual misorientation angle method' (SMMA method). The cluster method is validated by comparing the obtained results with the results of the SMMA and triplet methods

Application of fractional order theory of thermoelasticity in an elliptical disk and associated thermal stresses

In this article, a time fractional-order theory of thermoelasticity is applied to an isotropic homogeneous elliptical disk. The lower and upper surfaces of the disk are maintained at zero temperature, whereas the sectional heat supply is applied on the outer curved surface. Thermal deflection and associated thermal stresses are obtained in terms of Mathieu function of the first kind of order 2n. Numerical evaluation is carried out for the temperature distribution, Thermal deflection and thermal stresses and results of the resulting quantities are depicted graphically

Application of Fractional Order Theory of Thermoelasticity in an Elliptical Disk and Associated Thermal Stresses

In this article, a time fractional-order theory of thermoelasticity is applied to an isotropic homogeneous elliptical disk. The lower and upper surfaces of the disk are maintained at zero temperature, whereas the sectional heat supply is applied on the outer curved surface. Thermal deflection and associated thermal stresses are obtained in terms of Mathieu function of the first kind of order 2n. Numerical evaluation is carried out for the temperature distribution, Thermal deflection and thermal stresses and results of the resulting quantities are depicted graphically

Microstructure Evolution and Abrasive Wear Behavior of Ti-6Al-4V Alloy

This paper investigates the effect of quenching and aging treatment on microstructure and abrasive wear of Ti-6Al-4V alloy. The as-received alloy was solution treated at 1339 K, then oil quenched, followed by aging at 823 K for 4 h (14,400 s). The microstructures of as-received and quench-aged specimens were characterized by using optical microscopy, scanning electron microscopy, energy dispersive spectroscopy, and electron backscattered diffraction techniques. The as-received specimen consisted of very fine alpha grains (average grain size 2 mu m) with beta phase uniformly dispersed throughout. The microstructure of the quench-aged specimen showed alpha plates (formed by the decomposition of alpha' during aging). The beta phase precipitated out of alpha' martensite during aging and hence was dispersed uniformly in the alpha matrix. Ti-6Al-4V alloy was quench-aged to achieve maximum hardness with a view that the increased hardness would lead to an improvement in abrasive wear behavior. Two-body abrasive wear tests were carried out on the as-received and quench-aged specimens using pin-on-disk apparatus with SiC as abrasive media (150-grit size). The effect of sliding distance and normal load on the abrasive wear behavior was studied. The wear resistance of the as-received specimen was greater than that of quench-aged specimen, while hardness of the as-received specimen was lower than that of quench-aged specimen. The abrasive wear behavior of Ti-6Al-4V alloy has been explained based on morphology/microstructure of the alloy and the associated wear mechanism(s)

Electroreflectance of thin film solar cells

The effect of Cu off stoichiometry and Zn alloying on the fundamental absorption region of Cu2CdSnS4 CCTS absorbers in complete solar cells has been investigated using electroreflectance ER spectroscopy at room temperature. It is found that ER spectra consist of contributions from two different sources, one of which corresponds to band gap transition in the absorber layer and the other to the interference effect in the window layer. ER measurements on CCTS samples reveal a near constant band gap energy of 1.37 1.38 eV and a relatively small broadening of 60 90 meV in the probed 0.8 lt;Cu Cd Sn lt;0.89 compositional range, in contrast to related kesterites Cu2ZnSn S,Se 4. The analysis of the band gap in Cu2 Cd1 amp; 8722;x,Znx SnS4 alloys yields a quadratic dependence on Zn content with a bowing parameter of 0.4 eV. Finally, the broadening parameters of the band gap transitions as well as their compositional dependence are evaluated and discusse

ENHANCED AQUEOUS SOLUBILITY AND IN VITRO DISSOLUTION OF THE ANTI-HYPERLIPIDEMIC AGENT USING SYNTHESIZED SOLID DISPERSION CARRIER

Objective: To improve ATN's solubility, permeability, and dissolution rate, pentaerythritol-eudragit®RS100 co-processed excipients (CE) and their potential as a solid dispersion carrier (ATN-CE-SD). Methods: The ATN-CE-SD was prepared using the solvent evaporation technique. The pure ATN, physical mixture, CE carrier, and optimized ATN-CE-SD was physico-chemically characterized using Scanning electron microscopy, Fourier transforms infrared spectroscopy, differential scanning calorimetry, powder x-ray diffractometry, solubility research, and in-vitro dissolution was used to evaluate solid dispersions. Results: Physical and chemical analysis showed that ATN-CE-SD formed via the involvement of weak intermolecular forces of attraction between CE carrier and ATN. The prepared solid dispersion showed the drug content around ~ 96.94 % w/w, indicating that the solvent evaporation method improved the encapsulation of ATN and, thus, enhanced its drug content. Compared to pure ATN(~ 0.11 mg/mL), ATN-CE-SD (1:2) significantly increased the aqueous solubility by around ~ 25-fold (~ 2.78 mg/mL), indicating solid dispersion improves the solubility of ATN. ATN-CE-SD enhanced the rate of dissolution of ATV (~ 65 %) compared to pure ATN (~ 25 %) and PM (~ 34 %). Likewise, ATN-CE-SD (1:2) improved the rate and extent of ATN (~ 60 %) across the biological membrane compared to pure ATN (~ 22 %) and PM (~ 32 %). The ATN-CE-SD (1:2) improved the dissolution efficiency by around ~ (57.31%) compared to pure ATN (~ 7.02%) and PM (~ 20.43%). According to the study, co-processed excipients could serve as a promising solid dispersion carrier and improve ATN's water solubility, permeability, and dissolution rate. Conclusion: Based on the results, it is possible to use synthetic solid dispersion carriers as alternatives to improve the low water solubility and permeability of ATN