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Aluminium matrix composites (AMC) are gaining wide popularity in various sectors due to their excellent properties which are synergic. Apart from strength, wear resistance of a material is also an essential criterion for the number of applications. Extensive studies are being carried out on the secondary processing of these materials to enhance the suitability of the AMC for engineering applications. In this study, initially, Al 2014 base alloy and their composites with 5, 10, and 15 wt.% SiCp fabricated by stir casting route were subjected to wear test. Based on the encouraging wear performance, the Al-10 wt.% SiC composite was further subjected to extrusion. Pin-on-disc sliding wear tests on the as-cast & extruded base alloy and the composite samples were carried out at a constant load of 20 N for a total sliding distance of 1000 m with a velocity of 2 m/s. Microhardness and porosity measurements were carried out besides the study of wear performance, such as coefficient of friction and wear by weight loss. The worn surfaces were analyzed both by optical and scanning electron microscopes. The effect of particle addition, extrusion, porosity, and microhardness on the wear performance of the samples was discussed. Among the samples studied, the Al-10 wt.% SiC composite extruded at a ratio of 8:1 is found to have the highest wear resistance.

This research work is to explicit the surface morphology, material composition and crystal structure of a closed-cell aluminium foam subjected to various treatments such as heat treatment (HT), cryogenic treatment (CT) and cryogenic heat treatment (CHT). The closed-cell aluminium foam utilized for this research is made of Al 6101 aluminium alloy with high purity. The microstructure, material composition and crystal structure of the treated samples are evaluated by a high-resolution scanning electron microscope, energy dispersive X-ray technique and X-ray diffraction technique, respectively. From the results, significant observations were made in the surface morphology of the Al 6101 foam samples subjected to various treatments.

Accidents are the leading causes of injuries and fatality rate raises vulnerably in automobile. The need of additional safety options to reinforce the active safety in vehicles. The foremost reason behind the accident is drivers fault and braking inefficiency. Automatic braking and additional features are incorporated in high cost vehicles not in low cost vehicles. The research is carried on the low cost vehicles to prevent drivers from collisions which are cost effective. Therefore the result suggested that more than 16 to 20 percentage of collision occurs due to driver’s health issues. The drivers fault is monitored and braking efficiency is enhanced by using the proposed system. The proposed system used to monitor the condition of the driver by inserting sensor in steering wheel for pulse measuring. The mechanical plunger for actuating the braking system is incorporated to prevent the collision during health issues. During abnormal condition of the driver the pulse sensor gives the signal to the controller to activate the hydraulic plunger connected to the brake pedal. The actuator which is placed above the brake pedal and it is compressed when the signal from the controller to compress the brake pedal during demand. The proposed system analysis the condition of driver to enhance the protection to the driver and retards the vehicle speed to prevent the accidents.

Electroless composite coatings with various concentrations of reduced graphene oxide (rGO) particles were deposited onto mild steel substrate. The effects of adding rGO particles by varying their concentration from 0 to 100 mg/L on morphology, composition, microhardness, adhesion, wear and friction of the electroless composite coatings were investigated. Among the various parameters that influence the tribological behavior, sliding velocity was varied within a specific range for definite concentrations of rGO to obtain enhanced wear resistance in this study. The micrographs of the worn surfaces and indented spots were examined for the nature of wear mechanism and interfacial adhesion. The wear rate increased with increasing sliding velocity but was relatively stable for coatings with lower concentrations of rGO.

Protective coatings have been gaining prominence in research related to graphene based compounds over the recent years. The present study aims to reveal the novel anti-corrosive properties of the coatings achieved by co-depositing the carbon allotropes. Electroless Ni-P-rGO coatings were successfully obtained on low carbon steel substrates by adding various concentrations of rGO particles to the conventional electroless Ni-P bath. The coated specimens were characterized for its morphology and composition corroborated by X-ray diffraction and microhardness analysis. The corrosion and erosion corrosion behaviour of the Electroless Ni-P-rGO coatings were studied using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) in 3.5 wt% sodium chloride solution. The erosion corrosion behaviour of the coatings for different concentrations of rGO particles was examined using a slurry pot tester. The addition of rGO particles had considerably improved the corrosion and erosion resistance and the best results were achieved at an optimum concentration of 50 mg/L of rGO in the bath.

This paper investigates the effects of surfactants on microhardness, scratch, wear and friction behaviour of the Ni-P-nano-TiO 2 composite coatings. Nano TiO 2 particles were co-deposited with electroless Ni–P coating on low carbon steel substrates in the presence of anionic and cationic surfactants-sodium dodecyl sulphate (SDS) and dodecyl trimethyl ammonium bromide (DTAB) respectively. Results revealed that at an optimum concentration of the surfactants, the coatings obtained a smoother surface, low frictional coefficient, enhanced microhardness and high wear resistance. The findings of scratch test showed that the composite coatings with surfactants exhibited the ability to withstand higher critical load and lower penetration depth. This can be ascribed to the reinforcing action of co-deposited TiO 2 nanoparticles in the composite coatings. The cationic surfactant DTAB contributed to the increase in weight percentage of TiO 2 in the Ni–P matrix considerably. At critical micelle concentration (CMC) value of the DTAB surfactant, the coatings had the highest weight percent of incorporated TiO 2 and showed a better homogenous distribution.

Aluminium alloy foams are highly utilised material because of their high ductility, low density, high thermal conductivity, and lesser cost. Cryogenics would be an unconventional methodology amongst the material fields for the improvement of mechanical properties. The cryogenic treatment of non-ferrous alloy foams will also produce more wear resistance and longer durability products. This research is to investigate the mechanical properties and microstructural characteristics of closed-cell aluminium foam made of Al 6101 aluminium alloy with different heat regimes namely heat treatment (HT), cryogenic treatment (CT), and cryogenic heat treatment (CHT). The experimental results reveal that the cryogenic treatment of Al 6101 foam decreases the elastic limit and leads to brittleness. A comparison of the stress-strain curve emphasises that the increase of brittleness in the CHT regime is due to the reduction of the elastic region and also the scanning electron microscopic (SEM) images prove that the cryogenic treatment changes the morphology of aluminium alloy foam.

This article considers an experimental study of Taguchi’s parameters design to maximize the corrosion resistance of electroless Ni-P-nano-TiO2 on low carbon steel substrate. The experiments were carried out based on Taguchi’s L9 orthogonal array considering four coating parameters of three levels each namely, Bath Temperature, pH of bath, Bath Loading, and concentration of TiO2. Scanning Electron Microscope (SEM) equipped with Energy Dispersive X-ray Spectroscopy (EDS) facilitated the study of the surface morphology and the chemical composition of the coatings. Corrosion performance of the deposits was evaluated by Tafel polarization technique in 3.5 wt. % of NaCl solution. The observation shows that pH level has more significant influence on the corrosion behavior of the composite deposit. The experimental study revealed that the optimum conditions are A3B3C2D1 (Temperature of 88° C, pH of 6, bath loading of 0.5 dm2/l, and TiO2 concentration of 2 g/l).

In this paper, the effects of two different types of surfactants on the properties of Ni-P-TiO2 coating on low carbon steel substrate were investigated. Sodium dodecyl sulphate (SDS) - anionic surfactant and dodecyl trimethyl ammonium bromide (DTAB) - cationic surfactant were used for the deposition. Deposits were characterized by a high resolution scanning electron microscope (HR-SEM), an energy dispersive X-ray spectrometer (EDS), and X-ray diffraction (XRD) to study the surface morphology, composition and crystal structure of the coatings respectively. In addition, the influence of surfactants on the corrosion behaviour of Ni-P-TiO2 coatings was also examined using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) in 3.5wt.% sodium chloride solution. The results showed that at an optimum concentration of cationic surfactant DTAB, uniform distribution of TiO2 particles with no defects was observed. The corrosion properties were improved by the incorporation of TiO2 particles in the Ni-P matrix. The increase in corrosion resistance of the Ni-P-TiO2 coatings significantly depends on the surfactant and its concentration. � 2015 Elsevier B.V..