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The purpose of this paper is to research the durability of the adhesive‐poly(ethylene terephthalate) film joints.

The adhesive‐poly(ethylene terephthalate) joints are prepared with poly ethylene terephthalate film synthesised from thioglycolic acid, terpene hydrocarbon resin and acetone resolution at room temperature. These joints are characterised by methods of peel strength tests, energy dispersive X‐ray spectroscopy (EDX) and analysis of glass transition temperature (T_g) to examine their durability.

Peel strength tests and EDX analyses prove that water diffusion in different humidity aging conditions causes similar changes, namely having the time‐temperature equivalence at 45°C for 200, 300, 500 and 600 h, respectively, almost corresponding with those at 55°C for 100, 200, 300 and 400 h, respectively, and at 65°C for 50, 100, 150 and 200 h, respectively. The changes in EDX spectra of adhesive‐poly(ethylene terephthalate) film joints indicate that the rate of water penetration in the adhesive is faster than that in the poly(ethylene terephthalate) film. In humidity aging process, the decline ratio of peel strength of adhesive‐poly(ethylene terephthalate) film joints treated with Co⁶⁰ irradiation is lower than that treated with acetone washing or chemical treatment.

The paper shows that using EDX for analysis of durability of adhesive film joints is of significance to industrial process.

The purpose of this paper was to study the parameters affecting corrosion of the closed-loop oscillating heat-pipe with check valves (CLOHP/CV) in a system in clear that will be basic data to be used in future research. The majority of research focuses on the inner surface corrosion heat-pipe systems. The CLOHP/CV is commonly favored in cooling electronic devices, etc. Despite these common applications, limited reliable experimental research findings are available on the operation of the CLOHP/CV. Because of these reasons, the lack of detailed data, working fluids effect, working temperatures and duration of testing of the CLOHP/CV, this study focuses on determining the actual inner surface corrosion.

Seven types of copper tubes used in the CLOHP/CV set were sectioned to observe their inner surfaces. Seven different specimens with tube corrosion were examined by a visual inspection, scanning electron microscopy (SEM) and energy dispersive X-ray spectrometry (EDX). The technique for detecting metals solution in samples is based on the fact that ground state metals absorb light at specific wavelengths. Metal ions in a solution are converted to atomic state by means of a flame. In this study, concentration of copper particle in the working fluid was found by flame atomic absorption spectroscopy (Flame-AAS) and elements that occurred on inner surface tube were analyzed by EDX.

The analyses with SEM and EDX testing found that the character corrosion of inner surface of CLOHP/CV was pitting clearly. The analysis with Flame-AAS found that the concentration of copper particles in the distilled water and ethanol as working fluid is more than after 1,000 hours until 3,000 hours because of excess volume of oxygen in working fluid which causes many reactions at the beginning. When the oxygen decreases after 1,000 hours, it causes the reaction to decrease too and get the most concentration of copper particles, i.e. 18.57228 ppm or 0.40859 mg.

Corrosion-dependant maintenance must also be factored into the design. Producing reliable equipment that will become standardized and fixing the time for proper maintenance will require individuals that are knowledgeable about the materials that are going to be used in the design of such equipment. Nowadays, the lack of detailed data of working fluids effect, working temperatures and duration of testing of the CLOHP/CV focuses on determining the actual inner surface corrosion. Therefore, this research aimed to study the parameters affecting corrosion of the CLOHP/CV in a system in clear that will be basic data to be used in future research.

The purpose of this article is to establish why the wetting on PCBs with SnCu (HASL) and Snimm finishes in the presence of a flux is better than the wetting of those on a copper substrate. The practical aspect of the obtained results is the main goal of these investigations.

The authors applied the wetting balance method for the wetting measurements at 230 and 250°C, in nitrogen atmosphere, in the presence of the ORM0 type flux. The PCBs with the SnCu (HASL) and Snimm finishes were investigated in the state “as received”. To establish the wetting properties of the SnCu (HASL) and Snimm finishes on the PCBs, wetted by the investigated SnZnBiIn alloys, the SEM and EDX analyses were performed.

The authors obtained very good wetting results of the PCBs with the SnCu and Snimm finishes, wetted by the SnZn7Bi3In4 alloys. By applying the SEM and EDX methods, it was possible to establish that the barrier layer which was created during the HASL process between the copper and the SnCu solder is efficient enough to protect the copper against the influence of the Zn atoms from the SnZn7Bi3In4 solder. This is the reason for an improvement of the wetting properties. An immersion tin finish does not create such barrier layer with the copper. It results in a worse wetting than for the SnCu finishes but a better one than that for the copper. Immersion tin dissolves in the alloys during the soldering and this process delays the reaction between the copper and the Zn atoms from the SnZn7Bi3In4 solder.

It is suggested that further studies are necessary for the confirmation of the practical application, but they should be limited to the reliability of the solder joint performance.

The best wetting results of the PCBs with “tin finishes”, especially with SnCu, wetted by the SnZn7Bi3In4 alloy, at 230 and 250°C and in nitrogen atmosphere, suggest a possibility of a practical usage of the tin‐zinc‐bismuth‐indium alloys for soldering in electronics.

The wetting balance method combined with the SEM and EDX analyses were used as the quickest way to determine the mechanism of the better wettability properties in the case of the PCBs with the SnCu and Snimm finishes, wetted by the SnZn7Bi3In4 alloy, compared to those of the PCBs on the Cu substrate.

The filterable particles found in electronic solder fluxes vary considerably in both concentration and chemistry. Four fluxes from three manufacturers were examined, including both rosin fluxes and mildly activated resin fluxes. Individual particles were examined by optical light microscopy (OLM) and scanning electron microscopy/energy dispersive X‐ray spectroscopy (SEM/EDX). Finally, an automated SEM/EDX system was used to collect and summarise information about the size and chemistry of a hundred or more particles from each flux. The number of particles per microgram of flux was found to vary by two orders of magnitude (0.004 to 0.4 per μg). The particle diameters ranged from 0.2–20 μm with averages of 1–3 μm. A large fraction of the particles (33–75% by number) were organic substances not soluble in the flux. The bulk of the inorganic particles were composed of sulphates, silicates and metal oxides. Thus, some solder fluxes may be introducing several contaminant particles into each solder contact. These contaminants may affect the quality of the solder joint depending on particle size and composition.

TiN and TiAlVN films have been prepared by DC magnetron sputtering technique at room temperature. TiN target has been used to deposit TiN thin film under pure argon (100 percent Ar) gas. Additionally, Ti6Al4V alloy target has been used to deposit TiAlVN under nitrogen and argon gas (50 percent Ar and 50 percent N₂). In this paper, two substrate types have been used: stainless steel 304 and Si(100). This analysis has confirmed that the nitride films, (TiN/Si) and TiAlVN in both cases, have been produced. Energy Depressive X-ray Spectroscopy (EDX) measurement confirmed that the TiN/Si was stoichiometry, where the N/Ti ratio was about 1 with low oxygen contamination. The results obtained have indicated that the TiAlVN has more resistance to corrosion than TiN film in 3.5 percent NaCl at 25°C (seawater). Both films, TiAlVN/SS304 and TiN/SS304, have shown improved corrosion resistance compared with virgin 304 substrate. Microhardness was carried out using Vickers method; the microhardness values for TiN/SS304 and TiAlVN/SS304 were approximately 7.5 GPa and 25.3 GPa, respectively. The paper aims to discuss these issues.

The films were prepared by a DC magnetron sputtering system starting from high pure (99.99 percent) Ti6Al4V target (Al 6wt%, V 4wt% and balance Ti) in plasma discharge argon/nitrogen (50 percent Ar and 50 percent N₂) for deposition of TiAlVN film. Pure TiN target (99.99 percent) was used for preparation of TiN film in pure argon plasma. The diameter of target was 50 mm and the power applied for preparation of the two films was 100 W. A cylindrical high-vacuum chamber (Figure 2) made of stainless steel 316, with height 363 mm diameter, was fabricated locally. Scanning electron microscope images have been used to discover the films morphology. The composition of the films has been determined by EDX technique for films deposited on Si substrate. The electrochemical corrosion test was carried out using conventional three-electrode cell of 300 ml capacity by using Voltalab PGZ 301 system (France) using Tafel extrapolation method and electrochemical impedance spectroscopy techniques.

TiN and TiAlVN films have been prepared by DC magnetron sputtering technique without heating of the substrates holder. The effects of the composition of nitride films on mechanical and corrosion properties were investigated. The composition of the films has been determined by EDX technique. The effect of using titanium alloy (Ti with Al and V) on the composition and crystalline quality has been investigated. The microhardness is strongly dependent on the addition of the Al and V elements, and it consequently improves mechanical proprieties. The microhardness values for TiN/SS304 were approximately 7.5 GPa and 25.3 GPa for TiAlVN/SS304. They indicate that prepared films prevent the aggressive action of corrosion media.

TiN and TiAlVN films have been prepared by DC magnetron sputtering method at room temperature. Titanium nitride film, especially TiAlVN, is an effective method to improve the corrosion resistance of SS304. TiAlVN film has exhibited enhanced corrosion resistance and higher microhardness. Independent time-of-flight elastic recoil detection analysis has been used to determine the composition of the film.

Nowadays, the usage of antibacterial textiles is very popular for different type of textiles. The silver (Ag) and zinc oxide (ZnO) are the most popular materials in order to improve antibacterial properties of textiles. The purpose of this paper is to investigate the possibility to produce Ag nanoparticle (NP), ZnO NP, Ag/ZnO NP composite materials in this experimental study.

It was investigated whether it was possible to produce Ag NP, ZnO NP, Ag/ZnO NP composite materials by hydrothermal method which was known as in-situ approach on the fiber. In addition, the colloidal silver (Ag+) was produced by electrolysis method, and used instead of process water which was necessary during generating of NPs on the fiber by this method. After whole applications, the samples were characterized by SEM, XRD, EDX analyses and the antibacterial activity of specimens was tested according to the ASTM E 2149-01 (gram-negative Escherichia coli). In addition, the resistance to the repeated washes of these antibacterial samples was investigated.

The production of NPs on the fiber was achieved. The results showed that the samples had sufficient antibacterial activity and this activity did not reduce depending on repeated washing treatments.

Because of usage of one type of fiber, it would be necessary to make researches on the different type of fiber, testing procedure (with different bacteria), washing replications and prescriptions.

During the process the temperature control is very important for the produced fiber. In addition chosen antibacterial test method is crucial for the testing of activity of product. Fiber must be washed at least once to remove unfixed NPs on the fiber.

The technical antibacterial polyester fiber was in-situ coated by hydrothermal method with Ag, ZnO, Ag/ZnO composite NPs.

The purpose of this paper is to study the structural and optical characterization of Al_x In_y Ga_1−x−y N quaternary epilayers, which were grown on c‐plane (0001) sapphire substrates with AlN as buffer layers using plasma assisted molecular beam epitaxy technique with indium (In) mole fraction y ranging from 0.0 to 0.1 and constant aluminum (Al) mole fraction x=0.06.

High‐resolution X‐ray diffraction rocking curve (HRXRD‐RC), scanning electron microscopy (SEM), energy dispersive X‐ray spectrometry (EDX), and photoluminescence (PL) spectroscopy have been measured on quaternary Al_x In_y Ga_1−x−y N thin films at room temperature.

HRXRD‐RC measurements confirmed that the Al_x In_y Ga_1−x−y N alloys had wurtzite structure. SEM images, element composition analysis by EDX, provided the evidence to show the existence of defects inside the samples contaminated by silicon from previous growth leading to nonuniformity of the epilayers, which caused decreased in the quality of the samples. PL spectra show reducing of the integrated intensity and an increasing red shift with increasing in content with reference to the ternary sample Al_0.06Ga_0.94N. The existence of a large amount of nonradiative recombination centers are responsible for the reduced the luminescence and the red shift provided evidence to an increase in composition inside the Al_x In_y Ga_1−x−y N quaternary alloys. Photoluminescence is used to determine the behavior of the near band edge emission represent the energy band gap of the quaternary films. The energy band gap decreases with increasing In composition from 0.01 to 0.1 mole fraction. This trend is expected since the incorporation of in reduced the energy band gap of ternary Al_0.06Ga_0.94N (3.529 eV). We have also investigated the bowing parameter of the variation of energy band gaps and found it to be very sensitive on in composition. A value of b=10.95 have been obtain for our quaternary Al_x In_y Ga_1−x−y N alloys.

This study on quaternary samples described in this paper, clearly indicates that the present of defects due to impurity contaminations has a dominant role in determining the structural and optical properties of Al_x In_y Ga_1−x−y N quaternary alloys.

The purpose of this paper is to investigate the surface corrosion products of copper alloys by non‐destructive techniques (NDT) and correlate them with their bulk composition.

Specimens of copper alloys, whose compositions were close to those of ancient copper‐based artefacts, were left to be corroded in simulated soil solution containing ammoniacal buffering solution of pH =10 in 1:1 ratio, in order to accelerate the corrosion rate. The elemental compositions of the surface corrosion products were determined versus time using X‐Ray Fluorescence Spectroscopy, and the surface morphology by Scanning Electron Microscopy with Energy Dispersive X‐Ray Micro‐detector methods, and the results were compared to the bulk composition, as measured by Atomic Absorption Spectroscopy and Inductively Coupled Plasma Atomic Emission Spectroscopy.

During the corrosion evolution of the copper alloys in the corrosive solution, transitional phenomena were observed such as an initial decrease of the copper concentration with a simultaneous increase of the concentrations of the secondary alloying metals (Sn, Zn and Pb). After 30‐60 immersion days, the alloy concentrations were stabilised.

The results of this research could contribute to the non‐destructive characterisation of copper‐based ancient artefacts (from which the taking of samples is not allowed).

The purpose of this paper is to investigate the inhibitive properties of black pepper extract (BPE) for aluminium in 1M hydrochloric acid (HCl) medium.

Gravimetric, electrochemical impedance spectroscopy, galvanostatic polarization, scanning electron microscopy with energy dispersive X-ray examinations (SEM-EDX) techniques were used to study the corrosion inhibitive study.

The gravimetric measurement indicates that inhibition efficiency shows direct proportional relation with concentration of inhibitor. The impedance results illustrates that there was a presence of protective layer of inhibitor adsorbed on the metal/solution interface. Polarization outcome showed that BPE is mixed type inhibitor. The existence of adherent layer of inhibitor on the Al surface was confirmed by SEM-EDX. Quantum chemical calculations were performed using the density functional theory at B3LYP/6-31G(d) level of theory to evaluate the activity of inhibitor molecules present in extract towards the corrosion inhibition of Al.

Due to the presence of large number of compounds in the extract, it becomes difficult to understand the most active compound responsible for inhibition. However, from gas chromatography mass spectrometry and quantum data, the approximation has been made that the major compound piperine present in the extract can be most probable component responsible for the inhibition activity. Further calculation of binding energy between Al and inhibitor molecules can be performed using Material Studio software.

The extract can be used in cleaning and etching solutions. It can be used to limit the loss of Al metal during etching process.

BPE can be used as a potential source of eco-friendly corrosion inhibitor for Al in HCl medium.

This paper aims to acquire the current density distribution on dissolving of Mg, MgZn₂ (η -phase), Mg₂Si (ß-phase) and Al₄Cu₂Mg₈Si₇ (Q-phase) surface in NaCl solutions.

MgZn₂ (η -phase), Mg₂Si (ß-phase) and Al₄Cu₂Mg₈Si₇ (Q-phase) are important intermetallic compounds found in aluminum alloys. Insitu scanning vibrating electrode technique (SVET) was used to acquire the current density distribution on dissolving of Mg, MgZn₂ (η -phase), Mg₂Si (ß-phase) and Al₄Cu₂Mg₈Si₇ (Q-phase) surface in NaCl solutions scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDX) was used to characterize the corroded surface.

SVET maps reveal that these compounds display characteristic dissolution features. Mg and MgZn₂ displayed localized anodic and cathodic sites while that of Al₄Cu₂Mg₈Si₇ > Mg₂Si displayed a diffused distribution of anodic and cathodic sites. The magnitude of the integrated anodic current densities on the compounds was noted to decrease with the progress of time, and the order of the magnitude of the current density with respect to the compounds is Mg > Mg₂Si > Al₄Cu₂Mg₈Si₇ > MgZn₂. SEM/EDX reveal that the highest mass loss recorded after the SVET test was manifested by Mg₂Si followed by MgZn₂ then Al₄Cu₂Mg₈Si₇.

Auxiliary information on the current density distribution on the corroding sample surface at the microscopic scale has been provided by SVET thereby taking care of certain limitations of traditional corrosion monitoring techniques such as gravimetric, hydrogen evolution and electrochemical measurements.