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By adding a Ce salt and an Nd salt to an anodizing electrolyte, modified anodic films are obtained on aluminum surfaces. This paper aims to study the effects of rare‐earth elements on the corrosion resistance of the anode film.

The crystalline film was studied by X‐ray diffraction. The methods of scanning electron microscope, energy dispersive X‐ray analysis, electrochemical polarization, and electrochemical impedance spectroscopy (EIS) were used to characterize the properties of the films.

After rare‐earth element modification, the pores of the porous layer were very evidently smaller, the anodic film was more compact, and the thickness and hardness of the films had increased. The corrosion resistance of the anodic films modified with rare‐earth elements clearly was improved in neutral, acidic, and basic NaCl solutions. Ce showed a better effect than Nd in increasing the corrosion resistance of the films, and the film modified with Ce+Nd showed the highest corrosion resistance. EIS analysis showed that the impedances of both the barrier layer and porous layer of the anodic films increased after modification with the rare‐earth elements, indicating that the anodizing process was affected by the presence of the rare‐earth elements.

The results presented in this paper offer a foundation for further research and application of rare‐earth elements in aluminum anodic oxide films.

This study aims to investigate the effect of different pore diameter and pore length on corrosion properties of anodic aluminum oxide (AAO) film.

AAO layer was produced by two-step anodization aluminum in oxalic acid. The surface morphology was investigated using field emission scanning electron microscopy. The pore diameters were ranging from 25 ± 5 to 65 ± 5 nm and the pore length ranging from 5 to 17 µm. The corrosion properties of the AAO films was analyzed by potentiodynamic polarization and electrochemical impedance spectroscopy tests. Corrosion properties and morphology of the anodic films depending on anodization times and pore expansion times were evaluated.

All highlights of this work can be summarized with the following specified below: more treatment with the protective barrier layer of the solution as the pore diameter increases depends on the morphology of the nanotube structured AAO layer. The excellent corrosion resistance renders AAO films without pore expansion very promising. The oxide layer thickness does not affect the corrosion resistance. The better corrosion resistance of AAO films at low pore length can be ascribed to the barrier layer thickness and the more homogeneous structure. The presence of defects for the higher pore length decreases its corrosion resistance.

The AAO films were fabricated by a two-step anodization method in oxalic acid. The anodization times and pore expansion times affect the corrosion performance. The AAO film without pore expansion has good corrosion resistance. The corrosion resistance decreases as the pore length increases.

The novel structures and properties of nanostructure and nanomaterials give people perfect artistic expression of feeling and sense, then the nanoart discipline is developed and is closely related on the nanotechniques. The many achieved novel nanostructures with strong anti-corrosion prepared by the anodization have been reviewed. The paper would raise public awareness of nanotechnology, nanomaterial and their impact on our lives.

Anodization is a very effective and simple technique to form various nanostructures of metal oxide. It includes hard anodization, mild anodization and pulse anodization. Many measures have been introduced anodization process to improve the quality of formed nanostructure and enhance its properties, such as anti-corrosion.

The formation mechanism of anodic aluminum oxide (AAO) by using the mild, hard and pulse anodization has been discussed. The pretexture process and many other measures have been taken in mild and hard anodization to improve the regularity of pore array and greatly accelerate the formation rate of AAO. The pulse anodization has been used to prepare the multilayer Y-branched AAO film, which exhibits steady rich and vivid structure colors and gives a very good artistic expression. Furthermore, many other metal oxide nanostructures such as TiO₂ and CuO have also been fabricated using the anodization techniques.

Various nanostructures of metal oxide prepared by anodization have been reviewed and are itself a perfect artwork in mesoscale. Also, many nanostructures have exhibited steady, rich and vivid structure colors and give people a very good artistic expression.

This paper aims to present new technological approaches of manufacturing of micromechanical gyroscope ring-sensitive element based on the nanoporous anodic alumina instead of traditional silicon technology. Simulation and the operation analyses of such elements have been performed.

The design of gyroscope represents a sensitive element on a glass substrate; in the center of a ring, there is a permanent magnet in a steel box. The sensitive element is made of profiled nanoporous anodic alumina consisting of an octagonal frame which is connected to a ring in the center with eight N-shaped spokes. The technology of the sensitive element fabrication involves the electrochemical formation of nanoporous anodic alumina substrate given the thickness and porosity and its chemical etching on the element topology. The basic parameters and the operation principle of the nanoporous alumina-sensitive element have been defined by finite element simulation.

It is shown that the resonance frequencies of the sensitive element change as functions of the alumina porosity. The main parameters of the nanoporous alumina-sensitive element have been compared with parameters of a silicon-sensitive element. Calculations have shown that the mechanical deformations of the von Mises are approximately lower by two times in the nanoporous alumina-sensitive element.

High-precision angular rate measurement will be achieved by reducing mechanical and electrical noises practically to zero through careful designing of a ring magnetoelectric gyroscope

The ring resonator made of nanoporous anodic alumina will allow to increase the threshold of sensitivity and stability of micromechanical gyroscope characteristics owing to the high precision of geometric dimensions, the stability of the elastic properties and the quality factor.

This paper aims to study the anodization of aluminum in a mixture solution of 1,3-propanediol solutions and 0.4 mol l⁻¹ H₃PO₄ at a low temperature.

The morphology and composition of the resulting anodic aluminum oxide (AAO) template was characterized by means of a scanning electron microscope in combination with an energy dispersive spectrometer.

Pore density and pore diameter both were found to be dependent on the temperature of anodization.

The resulting AAO templates exhibited uniform and regular pores with diameters that were significantly smaller than those found in AAO templates anodized at room temperature.

The high specific strength makes magnesium alloys have a wide range of applications in aerospace, military, automotive, marine and construction industries. However, its poor corrosion resistance and weldability have limited its development and application. Friction stir welding (FSW) can effectively avoid the defects of fusion welding. However, the microstructure, mechanical properties and corrosion behavior of FSW joints in magnesium alloys vary among different regions. The purpose of this paper is to review the corrosion of magnesium alloy FSW joints, and to summarize the protection technology of welded joints.

The corrosion of magnesium alloy FSW joints includes electrochemical corrosion and stress corrosion. This paper summarizes corrosion protection techniques for magnesium alloys FSW joints, focusing on composition, microstructure changes and surface treatment methods.

Currently, this research is mainly focused on enhancing the corrosion resistance of magnesium alloy FSW joints by changing compositions, structural modifications and surface coating technologies. Refinement of the grains can be achieved by adjusting welding process parameters, which in turn minimizes the effects of the second phase on the alloy’s corrosion resistance.

This paper presents a comprehensive review on the corrosion and protection of magnesium alloys FSW joints, covering the latest research advancements and practical applications. It aims to equip researchers with a better insight into the field and inspire new studies on this topic.

An investigation to evaluate the suitability of anodised aluminium as a substrate material has shown that the relatively high coefficient of thermal expansion of the aluminium caused the brittle cermet resistors to craze giving rise to unstable resistance values whereas PTF resistors appeared to suffer no ill effects. The work was implemented in conjunction with selection of low temperature thick film conductor and resistor inks to achieve the optimum combination of anodised aluminium substrate and ink system. These inks were then printed and fired on anodised aluminium, aluminium nitride and alumina substrates, and the physical and electrical properties of the inks and substrates compared. A combination of modest success, employing polymer resistors and cermet conductors, produced viable circuits with resistors of reasonable stability. A low power hybrid device, with surface mounted components, was employed to further validate the substrate/ink combinations in ongoing tests.

The paper aims to describe the Taguchi design method-based abrasive wear modeling of in situ AlB2 flake reinforced Al-4Cu matrix alloy composites.

The abrasive wear behaviors of the composite samples were investigated using pin-on-disk method where the samples slid against different sizes of SiC abrasive grits under various testing conditions. The orthogonal array, signal-to-noise (S/N) ratio and analysis of variance were used to study the optimal testing parameters on composite samples.

The weight loss of composites decreased with increasing grit size and percentage reinforcement and increased with increasing sliding speed. The optimum test condition, at which the minimum weight loss is obtained, has been determined to be A3B3C1 levels of the control factors. Deviations between the actual and the predicted S/N ratios for abrasive weight losses are negligibly small with 99.5 per cent confidence level.

This paper fulfils an identification of Taguchi method-based abrasive wear behavior of AlB2/Al-4Cu metal matrix composites produced by squeeze casting under various testing conditions.

Different types of wood (ash, oak and beech) have been activated by new activation method. The aim of this work is to study the effect of different types of wood on the physical and chemical properties of Ni/Pd coatings.

The wood was activated by ablation of the Pd target using pulsed laser deposition (PLD) technique. Different diagnostic techniques such as X-ray photoelectron spectroscopy (XPS), attenuated total reflection (ATR) spectroscopy and energy dispersed X-ray spectroscopy (EDS), in parallel with scanning electron microscopy (SEM) were used to achieve this goal.

The XPS technique confirmed that the highest concentration of Pd was found in the Pd/beech sample, which is associated to the texture of the beech wood substrate surface. EDS results confirmed the absence of any contamination related to electroless plating method. It is concluded that the wood morphology and its surface roughness play a conclusive role to obtain different quantity of metal by PLD and electroless plating methods.

Although several works have been performed to study the influence of substrates on the coated metals and away of the traditional methods in activating non-catalytic surface, in this paper, PLD method is used to obtain a good quantity of Pd distributed on the entire surface and inside the porous of the wood. This study could be considered as a step investigation for understanding the role of the wood substrate morphology on the physical and chemical properties of films. To our knowledge, there are no works of combining a coated Ni/Pd by electroless plating and PLD methods on wood.