Ruxandra Vidu; Andra Mihaela Predescu; Ecaterina Matei; Andrei Berbecaru; Cristian Pantilimon; Claudia Dragan; Mirela Sohaciu; Cristian Predescu
Abstract
Co-Ni nanowires arrays were obtained by electrochemical template synthesis in a polycarbonate track etched (PCTE) membrane. To diminish the effects of anomalous deposition observed in the Co-Ni system, the electrochemical deposition was performed from a solution containing nickel and cobalt in an atomic ...
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Co-Ni nanowires arrays were obtained by electrochemical template synthesis in a polycarbonate track etched (PCTE) membrane. To diminish the effects of anomalous deposition observed in the Co-Ni system, the electrochemical deposition was performed from a solution containing nickel and cobalt in an atomic ratio of 3:1. Electrochemical deposition was performed at constant potentials E = -0.8, -0.9, -1.0, -1.1, -1.2 V vs Ag/AgCl for 15 min. The structures were characterized electrochemically via cyclic voltammetry, chronoamperometry, and charge stripping. Co-Ni nanowires were characterized by scanning electron microscopy (SEM/EDAX) to assess the morphology and the composition of the Co-Ni alloy nanowires at different deposition potentials. Electrochemical and structural analysis provided details of their deposition kinetics, structure, and morphology, which would be used to build nanowires array with controlled structure and composition.
Sanjeet Kumar; Deepa Mudgal; Surendra Singh; Satya Prakash
Abstract
High temperature oxidation is the main cause for the degradation of materials used at elevated temperature which is responsible for the major shut down of turbines, boilers and incinerators used in large units. An attempt has been made to use Cr3C2-25%NiCr coating deposited by D-gun technique on Superni ...
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High temperature oxidation is the main cause for the degradation of materials used at elevated temperature which is responsible for the major shut down of turbines, boilers and incinerators used in large units. An attempt has been made to use Cr3C2-25%NiCr coating deposited by D-gun technique on Superni 600 alloy. These coatings are generally used for wear applications. This coating has been studied for oxidation at 900C under cyclic conditions. Sound and adherent coatings of 150-250 μm can be obtained by D-gun process. The bare and coated alloys were subjected to cyclic oxidation in air for 100 cycles. Weight change/area has been plotted against number of cycles and to monitor the oxidation kinetics. The scale formed after oxidation both on the bare and coated alloys has been examined using FESEM/EDX, XRD, and Cross-sectional/Mapping analysis. The weight gain by coated Superni 600 was found to be about 80% less than that of bare Superni 600. D-gun sprayed Cr3C2-NiCr coating has contributed to increase in the oxidation resistance of coated superalloy. These types of coatings can be developed for high temperature applications for both corrosion and erosion resistance.