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The aviation field requires a material with the ability to withstand severe environmental conditions. The purpose of this paper is to provide higher wear resistance and improve the lifetime of aircraft. Hence, it is vital to enhance the wear resistance and strength of the material.

In this investigation, the Az91D magnesium alloy was reinforced with lanthanum (La₂O₃) and cerium oxide (CeO₂) nanoparticles by stir casting and heat treatment process and the tribological and mechanical properties were analyzed.

The results showed the Az91D/CeO₂ composite exhibited higher density (1.96 g/cm3) and lower porosity (1.01%) compared to other materials due to the diffusion of CeO₂ nanoparticles in between the atoms of Az91D alloy. The hardness of Az91D/ CeO₂ & Az91D/ La₂O₃ was improved by 38% and 34%, respectively, compared to Az91D alloy owing to the reinforcing effect of hard nanoparticles. Further, the inclusion of nanoparticles decreased the mass loss and showed lower wear rate compared to the Az91D alloy due to the pinning effect of nanoparticles. In addition, the friction coefficient was observed in the order of Az91D > Az91D/ La₂O₃ > Az91D/ CeO₂. Moreover, the heat treatment displayed positive results on the properties of all the materials.

This work is original as the combination of cerium oxide nanoparticles with Az91D magnesium alloy is not tried by earlier investigators. Further, the comparative performance of both lanthanum and cerium oxide nanoparticles on the tribological and mechanical behavior of Az91D alloy has been analyzed for aviation application. This study will provide new information to the scientific world to increase the lifetime of aviation structures.

Aviation field requires a material with greater tribological characteristics to withstand the critical climate conditions. Hence, it is of paramount importance to enhance the wear resistance of material. AZ91D magnesium alloy is a light weight material used in the aviation field for the construction work. The purpose of this study is to augment the wear properties of AZ91D alloy by reinforcing with hard particles such as tungsten carbide (WC) and silicon dioxide (SiO₂).

In this work, three types of composites were fabricated, namely, AZ91D – WC, AZ91D – SiO₂ and AZ91D – (WC + SiO₂) by ball milling method, and the tribological properties were analyzed using pin-on-disc apparatus.

Results showed that the hardness of AZ91D alloy was greatly improved due to the reinforcing effects of WC and SiO₂ particles. Wear study showed that wear rate of AZ91D alloy and its composites increased with the increase of applied load due to ploughing effect and decreased with the increase of sliding speed owing to the formation of lubricating tribolayer. Further, the AZ91D – (WC + SiO₂) composite exhibited the lower wear rate of 0.0017 mm3/m and minimum coefficient of friction of 0.33 at a load of 10 N and a sliding speed of 150 mm/s due to the inclusion of hybrid WC and SiO₂ particles. Hence, the proposed AZ91D – (WC + SiO₂) composite could be a suitable candidate to be used in the aviation applications.

This work is original which deals with the effect of hybrid particles, i.e. WC and SiO₂ on the wear performance of the AZ91D magnesium alloy composites. The literature review showed that none of the studies focused on the reinforcement of AZ91D alloy by the combination of carbide and metal oxide particles as used in this investigation.

The effect of SBF artificial body fluid on microstructure and morphology characteristics of AZ91D alloy was investigated using OM, SEM and XRD. The effect of corrosion on mechanical properties also was researched.

The results show that the corrosion weight loss rate initially increased, then clearly decreased, and finally remained steady. Pits began to appear when the sample was placed in a corrosive environment for five days and pitting gradually increased with longer exposure time.

The pits, which made the grain boundaries indistinct, first appeared near the grain boundary area and then gradually increased in area.

The main mode of corrosion is pitting and the primary corrosion product, MgOH2, could be observed after five days of corrosion.

This paper aims to study both the mechanical properties and the corrosion behavior of the synthesized in situ (TiC-TiB₂) particulates/AZ91 magnesium matrix composite and compare the results with that of the conventional AZ91D alloy.

Scanning electron microscope (SEM) equipped with energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) were used to study the surface morphology and crystalline structure. Mechanical compression tests were used to investigate the mechanical performance according to ASTM E9-89a. The corrosion behavior of the synthesized magnesium alloy was examined using both electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques in dilute Harrison solutions.

The microstructure of the Mg composite showed a uniform distribution of reinforcing phases. Also, the reinforcing phases were formed without residual intermediate phases. The addition of titanium and boron carbides not only enhanced the mechanical properties of the matrix but also improve its corrosion behavior.

This is the first time that magnesium matrix composite has been to synthesized with TiC and TiB₂ particulates starting from starting from Ti and B carbides powder without adding aluminium using practical and low-cost technique (in situ reactive infiltration technique). This paper studies the corrosion behavior of synthesized Mg matrix in dilute Harrison solution and compares the results with that of conventional AZ91D.

This paper aims to investigate the inhibition effect of sodium silicate (SS), sodium alginate (SA) and sodium tungstate (ST) on the corrosion behavior of AZ91D magnesium alloy in 3.5 per cent NaCl solution through polarization curve test at room temperature, electrochemical impedance spectroscopy and weight loss measurement.

The influence of SA concentration on the inhibition efficiency of the corrosion inhibitor was mainly analyzed. The corrosion morphology and inhibition mechanism of the samples were also analyzed with scanning electron microscopy and energy-dispersive spectroscopy.

The results show that with the increase of SA concentration, the corrosion inhibition first increases and then decreases. When SA concentration is 0.03 mol/L, the inhibition efficiency is the highest, reaching 98 per cent. The adsorption film formed by SA and other deposition films produce a synergistic effect on the improvement of corrosion resistance of AZ91D magnesium alloy.

The adsorption film formed by SA with other deposition films produces a synergistic effect on the improvement of corrosion resistance of AZ91D magnesium alloy. With the increase of SA concentration, the corrosion inhibition first increases and then decreases. When the concentrations of SA, SS and ST are 0.03 mol/L, 0.015 mol/L and 0.02 mol/L, respectively, the inhibition efficiency of the inhibitor is the highest, reaching 98 per cent.

The aim of this work was to propose a method to prepare composite phosphate conversion coating (CPCC), including ternary phosphate conversion coating (TPCC) and binary phosphate conversion coatings (BPCC), with one-step chemical conversion and to reveal and compare the corrosion resistance between TPCC and BPCC.

In this work, a calcium–manganese–zinc (Ca–Mn–Zn) TPCC was prepared on the surface of magnesium alloy (MA) AZ91D with one-step chemical conversion method; for Ca-Mn-Zn@TPCC, its microstructure was characterized with scanning electron microscope observation and scanning tunneling microscope detection, and its composition was characterized with energy dispersion spectroscopy and X-ray photoelectron spectroscopy analyses. Particularly, the corrosion resistance of Ca-Mn-Zn@TPCC and its comparison with Ca–Mn, Ca–Zn and Mn–Zn BPCCs were clarified with electrochemical and immersion measurements.

Ca-Mn-Zn@TPCC, which was composed of Ca, Mn, Zn, P and O, exhibited a mud-shaped with cracks microstructure, and the average crack width, terrain fluctuation and coating thickness were 0.61 µm, 23.78 nm and 2.47 µm, respectively. Ca-Mn-Zn@TPCC provided good corrosion resistance to MA AZ91D; in NaCl solution, the total degradation of Ca-Mn-Zn@TPCC consumed eight days; corrosion products with poor adhesion peeled out from Ca-Mn-Zn@TPCC-coated MA AZ91D spontaneously. Besides, the corrosion resistance of Ca-Mn-Zn@TPCC was better than that of Ca-Mn@BPCC, Ca-Zn@BPCC or Mn-Zn@BPCC.

The successful preparation of Ca-Mn-Zn@TPCC on MA AZ91D surface confirmed the proposed method to prepare CPCC with one-step chemical conversion was feasible; at the same time, it was further confirmed that for phosphate conversion coating, ternary coating had better corrosion resistance than binary coating did.

To develop new eco‐environmentally friendly surface treatments based on cerate compounds as alternatives to the process involving toxic chromates for the corrosion protection of magnesium alloys.

A treatment process in which a surface was alkaline‐etched prior to ceria treatment is proposed. The process involves cleaning, etching in potassium hydroxide followed by treatment in ceria conversion coatings. The effect of surface preparation prior to ceria treatment on the corrosion resistance of AZ91D in 3.5 per cent NaCl solution was measured using AC impedance spectroscopy and DC polarization techniques. Surface examination was performed by scanning electron microscopy, energy dispersive X‐ray.

It was shown that the ceria treatment can be used as a localized corrosion inhibitor for alloy AZ91D in NaCl solution. The level of inhibition strongly depended on the cerium concentration. Moreover, ceria treatments improved the pitting corrosion resistance due to the formation of protective oxide films which act as a barrier to oxygen diffusion to the metal surface. According to the EIS and polarization measurements, alkaline etching in KOH is more effective in reducing the pitting corrosion of AZ91D than was HCl. It was shown that surface treatment in alkaline solution (KOH) prior to ceria treatments played an important role in inhibiting the active surface sites, rejecting the chloride ions from the surface and forming uniformly distributed oxide film.

Ceria conversion coatings seem very promising as alternatives to toxic chromating for the corrosion protection of magnesium alloys in NaCl solution.

The purpose of this paper is to examine the performance of cold-sprayed Zn15Al alloy coating whether it is capable of protecting magnesium alloy from corrosion, and to compare it with arc-sprayed Zn15Al alloy coating.

In this paper, Zn15Al alloy coating was prepared with CS-6000 cold spraying system and HDX-800 arc-sprayed system. Corrosion behaviors of the two kinds of coatings were examined with potentiodynamic polarization curves methods combined with SEM, EDS, XRD, etc.

Corrosion behavior of cold-sprayed Zn15Al alloy coating is superior to arc-sprayed Zn15Al alloy coating. The bonding strength and density of cold-sprayed Zn15Al alloy coating is much higher than that of arc-sprayed Zn15Al alloy coating. The cold-sprayed coating has a dense structure which separate magnesium from corrosion medium completely. The samples behave as Zn15Al instead of AZ91D alloy. The coating has a low probability of pitting corrosion comparing with cold sprayed Al coating through potentiodynamic polarization curve.

Cold-sprayed Zn15Al coating can be used to improve the anticorrosion performance of magnesium significantly and low down the risk of pitting corrosion of coating.

Cold-sprayed Zn15Al coating is an environmentally friendly anticorrosion method for light alloy, which is also the most effective way among thermal spray, chemical vapor deposition, sol–gel, plating and anodizing or microarc oxidation.

The present paper used cold spray method to deposit Zn15Al coating, which has an overwhelming performance both in physical and anticorrosion to traditional thermal spray method.

To improve the wear and corrosion properties of AZ91D magnesium alloy, a Cu_0.5NiAlCoCrFeSi high entropy alloy (HEA) was fabricated on AZ91D magnesium substrate specimens by laser cladding using elemental powders. The laser-clad coating consists of a fine dendritic structure of a simple BBC phase with nano-size precipitates. The hardness of the coating was some ten times higher than that of the AZ91D substrate and was even higher than that of the same HEA produced by arc melting. The laser-clad coating exhibited good wear resistance, with a wear rate five times lower than that of the substrate material in dry friction wear conditions. The main wear mechanisms of the substrate and the HEA coating were different, the former dominated by both abrasive wear and adhesive wear and the latter by oxidative abrasive wear. With regard to corrosion properties, the laser-clad coating exhibited a more positive corrosion potential and a lower corrosion current density than those of the uncoated substrate material.

The purpose of this paper was to prepare the cerium-based conversion coating on AZ91D magnesium alloy, and its compositions, micro-morphology, corrosion resistance and the chemical valence state of the film elements were investigated.

The methodology comprised preparation of coatings at different temperatures, which then were characterized using scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, an electrochemistry workstation and by means of X-ray photoelectron spectroscopy.

The conversion coating had a micro-cracked morphology. The conversion coatings were composed of MgO (or Mg-OH), CeO₂ and Ce2O₃. The best corrosion resistance of the cerium passivation film appeared when the treatment temperature was about 35°C.

The corrosion current densities of conversion coatings were lower by one to two orders of magnitude than the corrosion current density of the blank sample. The rare earth passivation coating prepared under the best condition could reduce the corrosion current to 3.548 × 10−6 A/cm2.