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This study is aimed to investigate laser irradiation effects on the surface, structural, and mechanical properties of iron samples. The prepared samples have been treated for multiple exposure times using continuous-wave diode laser with a wavelength of 532 nm in a laboratory environment. The structural as well as surface modifications of laser exposed targets are explored via scanning electron microscope and X-ray diffractometer. The SEM analysis revealed micrometer grain size, exfoliational sputtering, and crater formation, while XRD patterns were used to investigate d-spacing, and grain size of laser exposed samples. The mechanical characteristics of laser-ablated materials were examined using a micro Vickers hardness-tester, and microhardness has been explored as a function of increasing laser exposure time. It has been observed that grain size reduces while hardness of polycrystalline iron increases with increase in exposure time. [ABSTRACT FROM AUTHOR]

The present work encloses the deposition of three zinc selenide (ZnSe) thin films of thickness 175 nm, 243 nm, and 286 nm using thermal evaporation technique under a vacuum of 5 × 10−5 mbar. The deposited ZnSe thin films are characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), surface profilometer, ultraviolet (UV)-visible (Vis)-near-infrared (NIR) spectrophotometer and Raman spectroscopic measurements. The structure and morphology measurements reveal that the deposited ZnSe material is nanocrystalline having a cubic structure whose crystallinity increases with an increase in film thickness/evaporation rate. The optical band gap estimated from the optical transmission spectra of the films is found to be 2.62 eV, 2.60 eV, and 2.57 eV, respectively, which decreases with an increase in film thickness. The estimation and polynomial curve fit analysis of refractive index, extinction coefficient, and dielectric constant indicates that these physical quantities are fifth-order polynomial function of wavelength. The obtained results are compared and analysed for justification and application of ZnSe thin films. [ABSTRACT FROM AUTHOR]

Aluminum-based nanocomposites reinforced with carbon nanotubes have increased scientific attention in today's life. The dispersion quality was the critical aspect, which decides the homogeneous distribution of CNTs within the Al matrix as starting precursors. In this study, a new attempt has been made to obtain a uniformly dispersed Al-0.75% CNT precursor via combining ultra-sonication, cubic tumbler rod milling, and spray drying. This process was integrated with organic deflocculant (formulator) in specific proportion to transform as a semi-wet-based route. The effect of milling media on the morphology and interface structure of the as-produced composite precursor after all the processing steps was investigated through scanning electron microscope (SEM), high-resolution transmission electron microscope (HRTEM), X-ray diffraction (XRD) analysis, Raman spectroscopy, and Fourier transform infrared spectroscopy. The results reveal that the approach is effective in CNT dispersion in Al precursor, which shields the nanotube structure from damage for longer periods of milling time due to the organic formulator mixture, and also, the CNT retention in the Al precursor with minimum clustering is identified compared to the ball milling process. Carbon traces were confirmed in the as-produced composite precursor by this approach. [ABSTRACT FROM AUTHOR]