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This paper aims to obtain rare earth magnesium alloy with good adhesion and corrosion resistance.

In 353 K oil bath, cyclic voltammetry was used to study the electrochemical behavior of Pr(III), Mg(II) and Ni(II) in choline chloride-urea ionic liquid. The constant potential method was adopted for electrodeposition of Pr-Mg-Ni ternary alloy films. The content of Pr in the Pr-Mg-Ni alloy films changes with respect to the deposition potential, deposition time and concentration ratio of Pr³⁺:Mg²⁺:Ni²⁺. Response surface methodology was applied to optimize the conditions for obtaining high-quality deposition films.

The results showed that the reaction of Ni(II) to Ni is irreversible; this result can be verified by Tafel polarization curve and chronocoulometry curve. Its transfer coefficient on the platinum electrode of 0.32 and diffusion coefficient is 1.0510⁻⁶ cm².s⁻¹. Mg(II) and Pr(III) cannot solely be reduced to their elemental form, but they can be induced via codeposition by Ni(II). The result shows that under a voltage of −1.00 V, the alloy coating with even structure is obtained when the concentration ratio of Pr³⁺:Mg²⁺:Ni²⁺ is 1:1:1 and the deposition time is 20 min. Scanning electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy and other analyses revealed that the alloy coating is amorphous. Polarization curves of the cathode are tested, which manifest the lowest corrosion current density, stating which has good corrosion performance in alkaline solution and NaCl solution; this can be attributed to its dense film structure and good combination with the substrate.

It provides some technology for the production of corrosion-resistant materials.

The present research work aims to study the friction coefficient in functionally graded rapid prototyping of Al–Al₂O₃ composite prepared via fused deposition modelling (FDM)-assisted investment casting (IC) process. The optimized settings of the process parameters (namely, filament proportion, volume of FDM pattern, density of FDM pattern, barrel finishing (BF) time, BF media weight and number of IC slurry layers) suggested in the present research work will help fabricate parts possessing higher frictional coefficient.

Initially, melt flow index (MFI) of two different proportions of Nylon6-Al–Al₂O₃ (to be used as an alternative FDM filament material) was tested on the melt flow indexer and matched with MFI of commercially used acrylonitrile–butadiene–styrene filament. After this, the selected proportions of Nylon6-Al–Al₂O₃ were prepared in the form of the FDM filament by using a single screw extruder. Further, this FDM filament has been used for developing sacrificial IC patterns in the existing FDM system which was barely finished to improve their surface finish. Castings developed were tested for their wear resistance properties on a pin-on-disc-type tribo-tester under dry conditions at sliding conditions to check their suitability as a frictional device for industrial applications. In the methodology part, Taguchi L18 orthogonal array was used to study the effect of selected process variables on the coefficient of friction (μ).

It has been found that filament proportion, volume of FDM pattern and density of FDM pattern have significantly affected the μ-values. Further, density of the FDM pattern was found to have 91.62 per cent contribution in obtaining μ-values. Scanning electron micrographs highlighted uniform distribution of Al₂O₃ particles in the Al-matrix at suggested optimized settings.

The present methodology shows the development of a functional graded material that consisted of surface reinforcement with Al₂O₃ particles, which could have applications for manufacturing friction surfaces such as clutch plates, brake drum, etc.

This paper describes the effect of process parameters on wear properties of the Al–Al₂O₃ composite developed as a functionally graded material by the FDM-based pattern in the IC process.

The purpose of this paper is to investigate the microstructural changes and stress corrosion cracking behavior via two‐stage stressing u‐bent tests for T6 and T73 tempers of Al 7075 Alclad alloy.

Study was made of the effects of heat treatment; two‐stage stressing u‐bent, metallography, scanning electron microscopy, energy dispersive spectroscopy were employed.

The results showed that the T6 heat treatment formed some very fine transgranular and coarse intergranular precipitates containing two compositions of (Fe/Cu/Si‐rich) and (Mg/Si‐rich) phases. The T73 treatment also precipitated some fine transgranular precipitates and coarse intermetallics with a (Fe/Cu‐rich) composition. In T6‐treated samples, stress corrosion cracking (SCC) occurred after 155 days due to the high susceptibility of the grain boundaries. In T73‐treated samples, the SCC did not occur even after 210 days. The dissolution of the Alclad layer in the corrosive media increased pH values and left the sample in the passivation region, protecting the sample from further corrosion attack.

Based on microstructural and SCC resistance properties obtained by heat treatments, the T73 heat treatment with a tempering temperature of 107°C for seven hours as the first step and 170°C for 19 hours as the second step can be recommended for Al 7075 Alclad sheets.

The purpose of this study is to look into the hygroscopic and tribo-mechanical properties of a polypropylene/polyamide-6 (PP/PA6) blend and a PP/PA6/Boron sesquioxide composite.

The hygroscopic behaviour of the PP/PA6 blend and PP/PA6/Boron sesquioxide composite was studied using a water contact angle goniometer in this study. To validate the hygroscopic behaviour of the blend and composite, water contact angles and surface energy of the materials were investigated. Tensile strength and hardness tests were used to determine mechanical characteristics, and tribological experiments on a pin-on-disc tribometer were used to demonstrate the friction and wear rates of dry and water-conditioned blends and composites. The melting temperature of dry and water-conditioned composites was determined using DSC analysis.

The hygroscopic effect of the PP/PA6 blend was found to be minimal in the experiment, while it was relatively dominating in the PP/PA6/Boron sesquioxide composite. Tensile strength was found to be somewhat lower in blend and composite compared to virgin PP, whereas hardness was found to be higher in both blend and composite. The composite’s tribological testing findings were fairly outstanding, with the coefficient of friction (COF) and wear rates significantly reduced due to boron sesquioxide reinforcement. The reaction between boron sesquioxide and water molecules produced boric acid, which increased the tribological characteristics of the composite even further. Following 30 days of water conditioning, the weight of the blend increased by 3.64% and the weight of the composite increased by 6.45% as compared to the dry materials. After water conditioning, tensile strength reduced by 0.8% for the blend and 14.16% for the composite. Hardness was determined to be the same in the dry state and after water-conditioning for blend but dropped 1% for composite. As compared to blend, the COF and wear resistance of composite were 15.52% and 25.16% higher, respectively. After absorbing some water, the results increased to 28.57% and 34.9%, respectively.

The mechanical and thermal behaviour of polymer composites (particularly polyamide composites) vary depending on the surrounding environment. Tests were carried out to explore the effect of water treatment on the tribo-mechanical and thermal characteristics of PP/PA6/Boron sesquioxide composite. Water treatment caused polyamides to bind with water molecules, resulting in voids in the material. The interaction between boron sesquioxide and water molecules produced boric acid, which increased the tribological characteristics of the composite.

Aluminium metal matrix composites are used in automotive and aerospace industries because of their high performance and weight reduction benefits. The current investigation aims to focus on the development of the stir cast aluminium-boron carbide composites with enhanced mechanical and tribological properties.

The aluminium-boron carbide composites are produced by stir casting process. Aluminium alloy A356 is chosen as the matrix material and three sets of composites are produced with different weight fractions of boron carbide particles. Higher particle size (63 µm) of boron carbide is chosen as the reinforcement material. Aluminium-boron carbide composites are tested for mechanical and tribological properties. The effect of process parameters like load, speed and percentage of reinforcement on the wear rate are studied using the pin-on-disc method. The interaction of the process parameters with the wear rate is analysed by DesignExpert software using RSM methodology and desirability analysis. The coded levels for parameters for independent variables used in the experimental design are arranged according to the central composite design. The worn surface of the pin is examined using a scanning electron microscope. The phases and reaction products of the composites are identified by X-ray diffraction (XRD) analysis.

Aluminium-boron carbide composites reveal better mechanical properties compared to monolithic aluminium alloys. Mechanical properties improved with the addition of strontium-based master alloy Al10Sr. The ultimate tensile strength, hardness and compressive strength increase with an increase in the reinforcement content. The wettability of the boron carbide particles in the matrix improved with the addition of potassium flurotitanate to the melt. Uniform dispersion of particles into the alloy during melting is facilitated by the addition of magnesium. Wear resistance is optimal at 8 per cent of boron carbide with a load 20 N and sliding speed of 348 RPM. The wear rate is optimized by the numerical optimization method using desirability analysis. The amount of wear is less in Al-B₄C composites when compared to unreinforced aluminium alloy. The wear rate increases with an increase in load and decreases with the sliding speed. The wear resistance increases with an increase in the weight fraction of the boron carbide particles.

The produced Al-B₄C composites can retain properties at high temperature. It is used in nuclear and automotive products owing its high specific strength and stiffness. The main applications are neutron absorbers, armour plates, high-performance bicycles, brake pads, sand blasting nozzles and pump seals.

Al/B₄C composites have good potential in the development of wear-resistant products.

This study aims to develop a less weight high wear resistant material to fabricate brake components especially in automotive sector.

Effort was initiated to design and develop aluminium metal matrix composite by combining aluminium alloy AA6061 and zirconium oxide (ZrO₂) with the help of stir casting coupled with squeeze casting unit. Morphology analysis of advanced composite has been carried out by optical microscopy and scanning electron microscopy (SEM). The hardness of composites having different compositions was tested using Vickers micro hardness tester. The tribological property of the developed three specimens having different composition has been tested using pin-on-disc wear test equipment under dry sliding conditions. To obtain better understanding of wear mechanism, SEM image of worn-out surface was captured and analysed. SEM images and the corresponding Energy-dispersive X-ray spectroscopy (EDX) on the wear surface were carried out.

The optical and SEM images evidenced the existence of ZrO₂ particles along the metal matrix composite. Porosity values shows that the porosity level is acceptable as it falls below 7 per cent. Also, the finding proves that increase in the percentage of reinforcement particle instigates agglomeration on the AA6061 composites. Hardness test demonstrated that the inclusion of hard ZrO₂ particles leads to substantial improvement in hardness and the hardness value started deteriorating when the composition reaches 15 per cent. The wear test results substantiated the enhancement of tribological property due to the inclusion of distinct ZrO₂ particles. Also, despite of addition of reinforcements, the wear rate increased when the load increases. SEM images proved that AA6061/ZrO2-5 per cent composite fashioned steady-state mild and smooth wear. EDX spectrum analysis revealed the existence of ZrO₂ particles along with wear debris, which caused wear of 685 µm in AA6061/ZrO₂-15 per cent composite.

The developed material possesses low wear rate which is the unique property of composite and frictional force which is directly proportional to load but the coefficient of friction remains apparently constant. As a whole, investigations on developed composites introduce a new material which is suitable for manufacturing of brake components for automobile industry.