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This study aims to using Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy and scanning electron microscope/energy dispersive Xray spectrometer to identify different automotive coatings for forensic purpose.

Two four-layered samples in a hit-and-run case were compared layer by layer with three different methods. FTIR spectroscopy was used to primarily identify the organic and inorganic compositions. Raman spectrum and scanning electron microscope/energy dispersive Xray spectrometer (SEM-EDS) were further used to complement the FTIR results.

Two weak and tiny peaks in one layer found between two samples by FTIR, Raman microscope and SEM-EDS verified the result of differences. The study used the three instruments in combination and found it’s effective in sensing coatings, especially in the inorganic additives.

Using these three instruments in combination is more accurate than individually in multilayered coating analysis for forensic purpose.

The three different instruments all present unique information on the composition, and provided similar and mutually verifiable results on the two samples.

With this method, scientists could identify and discriminate important coating evidences with tiny but characteristic differences.

This paper aims to understand the effect of steadite in gray cast iron (GCI) cylinder liners performance (friction and wear) when lubricated with new lube oil formulations to verify if steadite can be reduced or suppressed from cylinder liners composition.

The paper presents an experimental approach to quantify the separated effect of lube additives and steadite content on GCI performance. Friction and wear of GCI samples with and without steadite were analyzed under lubricated conditions with a 5W30 lubricant and a base oil of similar viscosity under operating conditions similar to the ones observed at the top dead center of Otto engines. Scanning electron microscopy (SEM)-EDS analysis was used to evaluate wear and tribofilm formation.

The paper shows that steadite stabilizes friction coefficient and slightly reduces wear in the tests performed with base oil. However, its advantages are marginal in comparison to the ones provided by the fully formulated oil. Furthermore, SEM-EDS analyses of the wear track showed that steadite does not chemically react with zinc and sulfur compounds, reducing the tribofilm formation on the real area of contact and consequently changing the tribosystem behavior.

This paper covers an identified need to study the effect of lube additives and GCI composition using actual piston ring and cylinder liners under operating conditions similar to the ones observed at the top dead center of Otto engines.

A structural and textural characterization study has been performed to investigate the adherence of zeolite-based catalyst washcoated onto honey-comb-type cordierite monoliths. The supports were characterized by the scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS), X-ray diffraction (XRD) and Brunauer–Emmett–Teller (BET) techniques.

SEM/EDS provided quantitative estimate of the washcoated monolith as the elemental composition of catalyst coating. The XRD pattern deduced that the zeolite-based catalysts were successfully mounted on the cordierite support, showing the characteristic peaks of zeolites (Zeolite Socony Mobil–5; ZSM-5) at Braggs angles of 7.88°, 8.76°, 23.04°, 23.88° and 24.36°, whereas the characteristic peak of cordierite is seen at a Braggs angle of 10.44°.

The BET results proved that a monolayer of zeolite may serve the need for surface area and porosity. This was evident in the increase of surface area of washcoated support as against the bare support. The obtained isotherms were of Type IV, illustrating the presence of mesopores. The adsorption and desorption isotherm branches coincided over the interval 0 < P/P0 < 0.50 and 0 < P/P0 < 0.45, showing N₂ reversible adsorption for the two samples, respectively.

It was concluded that the composite materials which are ZSM-5 (Si/Al = 25) and precursors of the transition salts of copper, zinc and ceria powders were deposited on the catalyst supports, establishing the success of the coating procedure relative to the adherence of the catalyst compositions on the ceramic support.

The biomaterials are natural or synthetic materials used to improve quality of life either by replacing tissue/organ or assisting their function in medical field. The purpose of the study is to analyze the hydroxyapatite (HAP), HAP-TiO₂ (25 percent) composite coatings deposited on 316 LSS by High Velocity Flame Spray (HVFS) technique.

The coatings exhibit almost uniform and dense microstructure with porosity (HAP = 0.153 and HAP-TiO₂ composite = 0.138). Electrochemical corrosion testing was done on the uncoated and coated specimens in Ringer solution (SBF). As-sprayed coatings were characterized by XRD, SEM/EDS and cross-sectional X-ray mapping techniques before and after dipping in Ringer solution. Microhardness of composite coating (568.8 MPa) was found to be higher than HAP coating (353 MPa).

During investigations, it was observed that the corrosion resistance of steel was found to have increased after the deposition of HAP and HAP-TiO₂ composite coatings. Thus, coatings serve as an effective diffusion barrier to prohibit the diffusion of ions from the SBF into the substrate. Composite coatings have been found to be more corrosion resistant as compared to HAP coating in the simulated body fluid.

It has been concluded that corrosion resistance of HAP as well as composite coating is because of the desirable microstructural changes such as low porosity high microhardness and flat splat structures in coatings as compared to bare specimen.

This study is useful in the selection of biomedical implants.

This study is useful in the field of biomaterials.

No reported literature on corrosion behavior of HAP+ 25%- TiO₂ has been noted till now using flame spray technique. The main focus of the study is to investigate the HAP as well as composite coatings for biomedical applications.

The purpose of this paper is to describe the effect of indium alloying on the thermal fatigue endurance of Sn3.8Ag0.7Cu solder in low‐temperature co‐fired ceramic (LTCC) modules with land grid array (LGA) joints and the feasibility of using a recalibrated Engelmaier model to predict the lifetime of LGA joints as determined with a test assembly.

Test assemblies were fabricated and exposed to a temperature cycling test over a temperature range of −40‐125°C. Organic printed wiring board (PWB) material with a low coefficient of thermal expansion was used to reduce the global thermal mismatch of the assembly. The characteristic lifetime, θ, of the test assemblies was determined using direct current resistance measurements. The metallurgy and failure mechanisms of the interconnections were verified using scanning acoustic microscopy, an optical microscope with polarized light, and scanning electron microscopy/energy dispersive spectrometry (SEM/EDS) investigations. Lifetime predictions of the test assemblies were calculated using the recalibrated Engelmaier model.

This work showed that indium alloying increased the characteristic lifetime of LGA joints by 15 percent compared with Sn3.8Ag0.7Cu joints. SEM/EDS analysis showed that alloying changed the composition, size, and distribution of intermetallic compounds within the solder matrix. It was also observed that a solid‐state phase transformation (Cu,Ni)₆Sn₅(→ (Ni,Cu)₃Sn₄ occurred at the Ni/(Cu,Ni)₆Sn₅ interface. Moreover, the results pointed out that individual recalibration curves for ceramic package/PWB assemblies with high (≥ 10 ppm/°C) and low (≈ 3‐4 ppm/°C) global thermal mismatches and different package thicknesses should be determined before the lifetime of LGA‐type assemblies can be predicted accurately using the recalibrated Engelmaier model.

The results proved that indium alloying of LGA joints can be done using In‐containing solder on pre‐tinned pads of an LTCC module, despite the different liquidus temperatures of the In‐containing and Sn3.8Ag0.7Cu solders. The characteristic metallurgical features and enhanced thermal fatigue endurance of the In‐alloyed SnAgCu joints were also determined. Finally, this work demonstrated the problems that exist in predicting the lifetime of ceramic packages with LGA joints using analytical modeling, and proposals for developing the recalibrated Engelmaier model to achieve more accurate results with different ceramic packages/PWB assemblies are given.

This study aims to perform the surface treatment of synthetic α-Fe₂O₃ red iron oxide pigment with hydrolysate 3-aminopropyl silane (A) and colloidal silica (CS) and investigate the effects of surface-treated pigment on the styrene acrylic (SA) emulsion and polyurethane (PU) dispersion.

For this purpose, firstly red iron oxide particles were modified with A and CS separately in an aqueous medium. After isolation of the modified iron oxide were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS). Moreover, the degree of the dispersion stability of the modified pigment in coatings with SA emulsion and PU dispersion was investigated by using an oscillation rheometer. Loss (G''), storage (G') modulus, loss factor [tan(δ)] and yield stress (τ⁰) values were determined by performing amplitude and frequency sweep tests.

The τ⁰ in SA coatings decreases with the amount of used A and increases with the amount of used CS. The τ⁰ decreases as the amount of used A and CS in PU coatings increases. The use of CS on red iron oxide pigments causes storage modulus to increase in SA coatings at low angular frequencies, while it causes a decrease in PU coatings.

To the best of the authors’ knowledge, for the first time, the suspended state of the iron oxide hybrid pigment formed with CS in the coating was investigated rheologically in this study.

The purpose of this paper is to confirm the importance of using metal–organic frameworks (MOFs) in the field of corrosion control due to their potential use as corrosion inhibitors.

NH2–MIL–101(Cr), an amine-functionalized chromium-based MOF [Cr(III)-MOF], was prepared by solvothermal technique. Thereafter, Cr-MOF was used as an anticorrosion additive for mild steel (MS) in 1 m HCl solution. This inhibition behavior was tested by electrochemical tests including electrochemical impedance spectroscopy and potentiodynamic polarization (PDP).

Increasing the added amount of Cr-MOF enhances its inhibition performance, which attained 96.40% at 30 ppm. The obtained data from PDP measurements describe Cr-MOF as a mixed-type inhibitor. Based on SEM/EDS and FTIR analysis, the adsorption of Cr-MOF on the surface of MS that prevents MS corrosion has been demonstrated. Furthermore, Langmuir model is the most adequate adsorption isotherm for the obtained experimental data.

This study revealed that NH2–MIL–101(Cr), an amine-functionalized chromium-based MOF (Cr(III)-MOF), is a potential corrosion inhibitor for MS in 1 m HCl solution.

The seeker value is a crucial part of a navigation system, able to adjust the nitrogen airflow of the system so as to manipulate guiding and tailing movement. The paper aims to determine the causes of failure of the valve system.

In order to reduce friction and ensure the smooth operation of the valve, a new MoS₂ solid film lubricant cured at room temperature, was coated on the plunger surface of the valve. SEM, EDS, and FTIR analysis was conducted.

Through analysis it was found that the lock failure of the valves was caused by the absence of MoS₂ in the surface and softening and melding of the film at an extended electrifying.

The paper outlines the strategies to avoid lock failure – by improving the quality of the solid film lubricant and modifying the assembly process of the valve.

The purpose of this paper is to examine the tribological behavior of the synthetic chlorine‐ and fluorine‐containing silicon oil as an aerospace lubricant.

The chlorinated‐phenyl and methyl terminated silicone oil (CPSO), chlorinated‐phenyl and trifluorinated‐propyl with methyl terminated silicone oil (FCPSO) were prepared. Their physical properties such as saturated vapor pressure and the evaporation weight loss were evaluated. The tribological properties of the silicon oils under moderate load were investigated with an Optimol SRV oscillating friction and wear tester, as well as Four‐ball friction and wear tester according to the standard method of ASTM D 4172 under higher load. The elemental composition generated on steel ball surface were analyzed on a scanning electron microscope with a Kevex energy dispersive X‐ray analyzer attachment (SEM/EDS), and the chemical nature of elements on worn surface lubricated with FCPSO were studied by X‐ray photoelectron spectrometer (XPS).

It is found that the CPSO and FCPSO show good tribological behavior for steel/CuSn alloy tribological pairs and are superior to hosphazene (X‐1P) and perfluoropolyether in terms of friction‐reduction ability and anti‐wear performance. The anti‐wear performance of FCPSO as lubricants for steel‐steel contacts is superior to CPSO. The EDS results showed existence of F and Si on the worn surface with lubrication of FCPSO, while XPS results indicated the occurrence of tribochemical reaction of FCPSO with friction pair during sliding process with the formation of FeCl₂, FeF₂ and the absorption silicon oil films on the lubricated metal surface.

The results substantiate that chemical reactive elemental such as chlorine or fluorine, which is substituted into silicon oil, helps to improve the anti‐wear and load‐carrying capacity of the liquid lubricant. So the excellent thermal stability, low‐temperature fluidity, very low‐saturated vapor pressure and excellent lubricity for steel/CuSn alloy of the silicon oil of FCPSO and CPSO make it an attractive alternative to conventional liquid lubricant for space mechanism.

To investigate the effect of the metallization and solder mask materials on the solder joint reliability of low temperature co‐fired ceramic (LTCC) modules.

The fatigue performance of six LTCC/PCB assembly versions was investigated using temperature cycling tests in the −40‐125°C and 20‐80°C temperature ranges. In order to eliminate fatigue cracking in the LTCC module itself, large AgPt‐metallized solder (1 mm) lands with organic or co‐fired glaze solder masks, having 0.86‐0.89 mm openings, were used. The performance of these modules was compared to that of AgPd‐metallized modules with a similar solder land structure. The joint structures were analysed using resistance measurements, scanning acoustic microscopy, SEM/EDS investigation, and FEM simulations.

The results showed that failure distributions with Weibull shape factor (β) values from 8.4 to 14.2, and characteristic life time (θ) values between 860 and 1,165 cycles were achieved in AgPt assemblies in the −40‐125°C temperature range. The primary failure mechanism was solder joint cracking, whereas the AgPd‐metallized modules suffered from cracking in the ceramic. In the milder test conditions AgPd‐metallized modules showed better fatigue endurance than AgPt‐metallized modules.

This paper proves that the cracking in ceramic in the harsh test condition can be eliminated almost completely by using AgPt metallization instead of AgPd metallization in the present test module structure.