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The purpose of this paper is to present the results of an atomic force microscopy (AFM) based approach to local impedance spectroscopy (LIS) measurement performed on AA2024 and AA2024‐T3 aluminium alloys.

AFM‐LIS measurements were performed ex‐situ without the electrolyte environment, so in fact the electrical not electrochemical impedance was obtained.

Relative local impedance values recorded for AA2024 alloy during the researches carried out were maximally approximately three orders of magnitude higher than the ones obtained for age‐hardened AA2024‐T3 alloy. Moreover, in the case of AA2024‐T3 alloy, a region located in the interior of α crystals exhibited localized impedance one order of magnitude higher than that measured at its grain boundary when affected by intergranular corrosion.

The paper presents differences in localized impedance between grain and grain boundaries activity.

The lateral force mode of atomic force microscopy (AFM) was applied to conduct friction tests on a filled PTFE/PPS‐composite blend. This method distinguishes between the individual phases of the blend, i.e. carbon fibers, PPS‐particles, PTFE‐matrix and graphite flakes. The relative frictional behaviours of the different filler types were compared and the law of microfriction was discussed.

This paper seeks to report a preliminary study that was conducted in order to investigate the corrosion behavior of aluminum surfaces in aqueous solution in the presence of microorganisms. For this purpose, the fungus Aspergillus niger was tested in chloride‐containing aqueous media.

Weight loss and pH measurements were performed to verify the activity of the fungus on the aluminum surface and the atomic force microscopy technique was used to examine the surface after removing the biological film.

The pH of the media depended on the immersion time. Pitting attack was observed on the surface. The findings confirmed that the corrosion reaction of the aluminum was catalyzed by the presence of fungus and, simultaneously, the mean roughness of the aluminum surface was altered. After removing the biofilm, fungal hyphae hallmark was evident.

Up until low, relatively few studies have addressed biofilm attack on materials, and especially attack on metallic surfaces in media contaminated by fungi. Hence, this paper is important for its contribution to the body of knowledge about biofilm action on metallic surfaces.

This paper aims to presents a new method of investigation of local properties of conformal coatings utilized in microelectronics.

It is based on atomic force microscopy (AFM) technique supplemented with the ability of local electrical measurements, which apart from topography acquisition allows recording of local impedance spectra, impedance imaging and dc current mapping. Potentialities of the proposed AFM-assisted approach have been demonstrated on commercially available epoxy-coated electronic printed boards in as-received state and after six-year service.

The technique proved to be capable of identification, spatial localization and characterization of conformal coating defects.

The proposed approach can be utilized for assessment of protective film state in such demanding fields as electronics or electrotechnics where the classical techniques of anticorrosion coatings investigation cannot be employed due to small element dimensions and relatively low coating thickness.

The approach adopted by the author is novel in the field of organic coatings investigation.

The purpose of this paper is to ascertain chemical changes occurring at various stages involved in processing of silver‐based photoimageable thick films; and to determine ensuing topographical features which other wise appeared to be hindered in 2D scanning electron microscopy.

Surface sensitive techniques, viz. X‐ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) were used.

Interfacial adhesion of silver film with substrate (Al₂O₃) was specifically looked into with respect to role played by photoimaging (before and after exposure to ultra‐violet light). XPS results revealed occurrence of subtle chemical changes in terms of unsaturation to saturation in C−C bonding and also an interesting C−Al bonding which presumably improves mechanical adhesion of unfired film with the alumina substrate. AFM was carried out to examine the surface roughness, particle size, and microstructure of film which are very important from the standpoint of high‐frequency applications.

Surface sensitive techniques like XPS and AFM were exclusively used in order to characterize silver‐based photoimageable thick films.

The purpose of this paper is to demonstrate the I‐V characteristics of ZnO film on Si substrates with Ag buffer layer by conductive atomic force (C‐AFM).

An Ag buffer layer and Zn film was first deposited on silicon substrate by RF‐sputtering deposition method from high pure Ag and Zn target, respectively. Then, the deposited film was sintered in air at 500°C for 1 h.

The structures and morphologies of the prepared films were characterized by X‐ray diffraction (XRD), energy dispersive spectrum (EDS), atomic force microscopy (AFM), and C‐AFM. The results show that the prepared ZnO films with Ag buffer layer have a good crystallinity and surface morphology. Interestingly, the I‐V curve of ZnO film exhibited typical characteristics of semi‐conductive oxide under the conductive Ag buffer layer.

The paper demonstrates, by C‐AFM, that the ZnO/Ag‐buffer/Si exhibits excellent crystal structure, morphology and typical I‐V characteristics.

The purpose of this paper is to investigate the interfacial nanostructures and the adhesions of the stainless steel (S.S) coating to the polyurethane (PU) and polyvinyl chloride (PVC) leathers.

PU leather and PVC leather deposit S.S nano-films on the surface of PU and PVC leathers in this study. The interfacial nanostructures were investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The experimental results revealed that the surface roughness of the substrates had extremely important influence on the morphology of nano-films. The adhesions of the S.S coating to the PU and PVC leathers were investigated by the peel-off test.

The results showed that the adhesive performance of the S.S nano-films coating on PVC leather was better than that on the substrate of PU leather. Moreover, a weight loss of per peeling force calculating formulation is proposed to determine the bonding strength between the S.S films and the substrates.

In this paper, influence of different substrates on surface morphology of S.S coating was studied by SEM and AFM. Moreover, the weight loss of per peeling force calculating formulation was used to discuss the bonding strength between the S.S coating and the substrates. The research methods presented in this paper are of innovation significance to a certain extent.

The purpose of this study is to understand the inhibitor behavior of specific drug against mild steel corrosion and their adsorption mechanism on the surface.

Corrosion rates are influenced by the formation of inhibitor aggregates at the mild steel surface. Detail surface characterizations of mild steel have been studied before and after adsorption of drugs in 1N HCl solution. Scanning electron microscopy, atomic force microscopy and Fourier transform infrared spectroscopy were used to examine the effect of drug adsorption on steel surface.

Scanning electron microscopy analysis suggested that the metal had been protected from aggressive corrosion because of the addition of the inhibitors. Atomic force microscopy visualization confirmed the formation of protective layer on steel surface, resulting in the decrease in surface roughness with corrosion rates. The nature of metal surface has been analyzed by Fourier transform infrared spectroscopy.

The findings of this study will help us to understand the interaction of specific drugs with mild steel surface and their potential inhibition mechanism.

The purpose of this study is to design and develop a new functional coating system for aerospace AL7075-T6 alloy that would evaluate the mechanical properties of the coating.

This paper outlines the scratch adhesion characterisation of Cr/CrAlN coating using a combination of radio frequency (RF) and direct current (DC) physical vapour deposition (PVD) magnetron sputtering. The surface morphology, microstructure and chemical composition of the Cr/CrAlN film were evaluated by optical microscopy (OM), field emission scanning electron microscopy (FESEM) integrated with energy-dispersive X-Ray spectroscopy (EDX) and atomic force microscopy (AFM). The film-to-substrate adhesion was measured by a scratch test machine manufactured with a detection system, motorized stages, penetration depth sensors, optical microscope and tangential frictional load sensors.

The AFM and ultra-micro hardness results showed an increase in surface roughness to about 20 per cent and hardness to about 74 per cent. Moreover, the film-to-substrate adhesion strength of 1,814 mN was obtained with PVD deposition process.

The main limitation of this work is caused by PVD deposition process. Besides, surface defects such as pinholes contribute to a decrease in adhesion strength.

The higher hardness of CrAlN coating is used to improve the properties of softer aluminium substrates. This hardness prevents ploughing-induced wear and provides greater adhesion strength by preventing coating delamination.

Until now, CrAlN is coated only on ferrous alloys. It has not yet been tried on aluminium alloys. Moreover, coating functionality depends on higher adhesion and failure mechanisms involved in the film-to-substrate system, which is significant in aerospace applications.