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The work aimed to produce Ni-P-MoS2-Al2O3 on Al-7075 alloys with multiple attributes through an electroless (EL) plating route. The effects of additives (MoS2 and Al2O3) in the EL bath on the surface morphology, topography, hardness, composition (phase and elemental), roughness, wettability, and coating thickness were evaluated. Results indicate a substantial enhancement in microhardness of the EL-coated surfaces by 70% (maximum hardness = ~316 HV) using powders, and 30% (244 HV) without powders. The maximum coating thickness and water contact angle obtained with powders were 6.16 μm and 100.46°, respectively. The coefficient of friction for the samples prepared using powders was 0.12, and for the base material it was 0.18. The compositional analysis through EDS and XRD suggested the incorporation of a hard and lubricious layer on the EL-coated surface owing to the presence of different phases of Al, Mo, P, Zn, O, and S. Therefore, the resulting coating surfaces impart hardness, self-lubrication, hydrophobicity, and wear resistance simultaneously. [ABSTRACT FROM AUTHOR]

The present work deals with the fabrication of silicon carbide (SiC) reinforced Ti6Al4V metal matrix composites (MMC's) by a direct metal laser sintering process, followed by characterization of microstructures and evaluation of mechanical properties. Variable process parameters like laser power density [3.528–5.172 W/cm2 (×104)], SiC reinforcements (5%–15% by volume), and beam scanning speed (3500–4500 mm/min) and constant process parameters such as spot diameter (0.4 mm), hatching gap (0.2 mm), and layer thickness (0.4 mm) were considered to perform the experiments. The influence of addition of reinforcements on mechanical and physical properties of fabricated samples as compared to Ti6Al4V was examined. Field emission scanning electron microscope images show good metallurgical bonding between reinforcement and matrix. The presence of intermetallic compounds formed during the sintering process was detected by x-ray diffraction, which enhances the mechanical properties of the fabricated samples. Density of sintered samples increased on the increment in laser power density but decreased with an increase in the percentage of SiC in the mixture. Mean value of coefficient of friction was found in the range of 0.157–0.115 in a testing duration of 10 min, showing improvement in the wear resistance property as compared to Ti6Al4V. The improved mechanical properties and surface characteristics result in the formation of effective MMC's for various engineering applications. [ABSTRACT FROM AUTHOR]