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Electro-induced hydrophilicity of the Ag/TiO₂ nanostructure has been reported in this study. In this work hydrogen plasma bombarded Ag/TiO₂ nanostructure was created using a sequential process including chemical vapor deposition and plasma bombardment.  X-ray diffraction and X-ray photoelectron spectroscopy were used to analyze structure and chemical states of the sample. The prepared Ag/TiO₂ heterostructure has enhanced visible-light-induced hydrophilicity comparing to pure TiO₂. The electro-induced hydrophilicity of the samples was also examined by creating the comb like electrodes on the prepared Ag/TiO₂. A super-hydrophilic surface was achieved by applying an electric bias voltage on the electrodes.

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The purpose of this paper is a qualitative evaluation of the mechanical properties of titanium aluminum nitride (TiAlN) hard nanostructured coatings applied on cutting tools using X-ray diffraction (XRD). Deposition of TiAlN and TiN nanostructured coatings were carried out by a pulse DC plasma-assisted vapor deposition (DC-PACVD) and a high power impulse magnetron sputtering (HIPIMS) machines. At first, for enhancement the adhesion of TiAlN nanostructured coating on the steel substrate, TiN inter-layer was deposited for the all samples. Nano-indentation, micro-hardness tester, and field emission scanning electron microscope (FE-SEM) were used in order to measured and compare the qualitative results with the real and experimental values. The results indicate that XRD pattern and their analysis can be a suitable qualitative method to evaluate the mechanical properties of the coatings. The lattice parameter, micro-strain, residual stress, texture coefficient, the crystal grain size and density of dislocation are used to demonstrate the relationship between the mechanical properties of the coatings and the XRD patterns. As a result, this method can be used as non-destructive and inexpensive method for quantitative comparison and evaluation of mechanical properties of thin film materials.

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Residual stresses reduce life time of welded joints and change the welded structure formation. Residual stress is stresses that remain in the body some specific operation like welding and is available when body is not under external loads. Different methods are available for residual stress relieved in any welded samples. In this research, samples A, B and C have been prepared and welded. Stress of Samples A and B have been relieved using heat treatment method and ultrasonic method, respectively. Also, no operation has been taken on the sample c. for different amount of residual stress of each sample, hole drilling method used and amount of residual stress in welding heat affected area of each sample determined. Results show that residual stress in ultrasonic method is for less than heat treatment method. To validate the results the x-ray diffraction method was also used and results of this method show that sample with ultrasonic stress, stress reliving had no peek in 2Ө angles, but for sample with heat treatment stress reliving had a peek in 137° that shows some residual stress.

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In this study, microstructure, microhardness and residual stress in the butt jointed friction stir welded aluminum alloy 2024-T351 plates with different tool’s rotational and traverse speed is studied. According to the 2024-T351 aluminum is a heat treatable alloy, Hardness test results showed that increasing rotational speed or decreasing traverse speed of the tool reduced hardness in the weld zone. Then, using standard X-ray diffraction, which is a non-destructive method, residual stress in the welded samples is determined. A thermal model of friction stir welding process is simulated by using finite element method in the ABAQUS software. Comparison of residual stress results that obtained from the numerical solution with experimental measurements show that, the numerical model can predict the residual stress fields in friction stir welding joints reasonably. The results show that, increasing rotational speed, cause to higher residual stress in the weld zone, due to generation the higher thermal gradient and also, The higher tool traverse speed will induce a greater high-stress zone with a higher stress value in the weld, because of, a lower heat input and result in the relatively harder metal in the weld zone, causes a greater resistance to the plastic extrusion.

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In the current work, a modified method of friction stir process (FSP) based on ultrasonic vibration and modified FSP tool design was developed to disperse multi-walled carbon nano-tube (MWCNT) throughout nylon 6 matrix. To this end, Field emission scanning electron microscopy, X-ray diffraction, Vickers’ micro-hardness, and visual inspection were used to evaluate the fabricated nano-composites. Also, a modified design of FSP tool together with ultrasonic vibration were used to improve the impact and efficiency of FSP. Several experiments were conducted to approach an optimum range of FSP parameters (rotational speed and traverse speed). The scanning electron microscopy observations and X-ray diffraction patterns (XRD) declare that MWCNT was dispersed homogeneously throughout nylon 6 matrix. Micro-hardness results illustrate that homogeneous dispersion of MWCNT throughout nylon 6 matrix results in 33% increase of micro-hardness. In general, the obtained results declare that ultrasonic vibration causes an increase in traverse speed and production speed of nano-composite without affecting the homogeneous dispersion and hardness of nano-particles throughout the matrix. Also, it is clear that ultrasonic vibrations did not noticeably affect superficial form of nano-composites due to low traverse speeds used in ultrasonic assisted friction stir process.

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In recent years, measurement of residual stress by ultrasonic method is developing because of nondestructive nature, portable equipment and being cheap and fast. In this research, the Capability of ultrasonic method by using longitudinal critically refracted or Lcr wave in measurement of longitudinal welding residual stress has been scrutinized. For this purpose, two plates of aluminum alloy series 5000 were joined by TIG welding method. Measurement of longitudinal residual stress by ultrasonic method was done in closeness of surface via 5 MHz transducers based on acoustoelasticity theory. In order to create Lcr wave and transmit it into specimen, an ultrasonic wedge was made based on Snell’s law. Also a triaxial table was used to control the wedge movement and keep the pressure on it fixed. In order to calculate residual stress and increase in accuracy, acoustoelastic constant for each three welding zones, including weld metal, HAZ and base metal was obtained separately from uniaxle tension test. In order to validate ultrasonic method results, measured longitudinal residual stress by x-ray diffraction method in 5 points on the specimen surface was used. Finally after comparing the results of two used methods with each other, good agreement was seen which indicates the good ability of ultrasonic method in measurement of longitudinal residual stress.

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Parkia biglobosa starch was subjected to different heat-moisture treatment (HMT) at different moisture contents (15, 20, 25, and 30%) at 110^oC for 16 hours. The content of resistant starch (RS) was the lowest (33.38%) in the untreated native Parkia and increased in the samples with HMT-15 (37.79%), HMT-30 (39.64%), HMT-25 (46.63%), and HMT-20 (50.14%), showing significant increase (P < 0.05) in RS following the HMT. There was a reduction in the swelling power and pasting properties of HMT starches, but the solubility of the HMT starches was higher than that of untreated native starch. Differential scanning calorimetry and the changes in the X-ray diffraction (XRD) patterns confirmed the effect of HMT on Parkia starch. Therefore, replacing native Parkia with heat-moisture treated Parkia starch leads to the development of new products from RS-rich powder with high RS levels and functional properties.

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In this study, a non-distractive method of x-ray diffraction (XRD) was used to determine residual stress of rolling mill rolls made of graphite steel (GSH48). This method utilizes the variations of distance between crystal planes as strain. The determination of residual stress was performed samples in different depths before and after conducting ultrasonic peening technology. In UPT process, impacts were exerted on the workpiece ball tool, resulting in the improvement of some mechanical properties such as residual stress by creating work hardening and compression. After the simulation and manufacturing of ultrasonic vibratory tool and then the installation of that on lathe machine, UPT operations were conducted on the prepared samples. Measuring residual stress from surface to 0.5 mm depth was performed before and after the UPT process. After the numerical simulation of the UPT, the distribution of experimental residual stress and numerical simulation was compared that the results suggested the increase of compressive residual stress about 0.4 mm from the surface after the UPT process. The rise of compressive residual stress in the rolling mill rolls leads to the increase of their strength and fatigue life and as a result, their working efficiency is boosted. After the UPT process, the grain size of the surface was calculated from the model of the x-ray diffraction using Viliamson-Hall relation that grain size was obtained 60.2 nm. The refinement of surface structure arises because of displacement arrangement again due to vibration with high frequency and severe plastic deformation after the UPT process.