The subject of this work is Ni50Mo40Ti10 alloy produced by mechanical alloying and subsequent heat treatment. The obtained material was tested as electrode for the hydrogen evolution reaction (HER) in an alkaline environment. The results were compared with those obtained for the Ni50Mo50 catalyst. Electrochemical characterization was carried out by the steady‐state polarization method and the electrochemical impedance spectroscopy (EIS). On the basis of the results of the EIS measurements, the average rate constant of the HER was determined. The calculated values of surface roughness factor, Rf, allowed to evaluate the true catalytic effect of the investigated electrode material. It was stated that Ni50Mo40Ti10 alloy annealed at 1173 K exhibits the higher electrocatalytic activity for the HER compared with the Ni50Mo50. The increase in the intrinsic activity could be attributed to the presence of NiMo intermetallic phase and Ni(Ti) solid solution. Copyright © 2014 John Wiley & Sons, Ltd.

This study was undertaken in order to obtain and characterize the corrosion resistance of Zn-Ni+Ni composite coatings. The influence of thermal treatment on surface morphology, phase composition, and corrosion resistance of Zn-Ni+Ni coating was investigated. The Zn-Ni+Ni coating was deposited under galvanostatic conditions (j = 40 mA cm −2 ). Thermal treatment was carried out in argon atmosphere. The surface morphology of Zn-Ni+Ni coatings was carried using a scanning electron microscope (JEOL JSM-6480) and the surface chemical composition was determined by the EDS method. Structural investigations were conducted by X-ray diffraction method. The studies of electrochemical corrosion resistance were carried out in a 5% NaCl solution, using potentiodynamic and scanning vibrating electrode (SVET) methods. On the grounds of corrosion investigations, it was stated that thermal treatment improves both total and localized corrosion resistance of Zn-Ni+Ni coating in a 5% NaCl water solution. The higher corrosion resistance of the thermally treated Zn-Ni+Ni coating could be attributed to the increase in the amount of zinc bonded to nickel in the form of Ni 2 Zn 11 and Ni 5 Zn 21 intermetallic phases. The SVET analysis indicated that thermal treatment of Zn-Ni+Ni coating causes a decrease in the number of corrosion centers on their surface area.

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Precipitation hardened magnesium-rare earth alloys offer attractive properties for the aerospace and racing automotive industries. The most successful magnesium alloys developed to date have been those based on the Mg-Y-Nd system identified as WE54 (Mg-5.0wt%Y-4.1wt%RE-0.5wt%Zr) and WE43 (Mg-4.0wt%Y-3.3wt%RE-0.5wt%Zr), where RE represents neodymium-rich rare earth elements. Precipitations sequence in WE-system alloys involved the formation of phases designated β”, β’, β1 and β depending on the ageing temperature. WE54 alloy with the equilibrium β-phase exhibits good ductility and medium tensile strength. The β phase precipitated in Mg-Y-Nd alloy during ageing at 300 °C was studied using X-ray diffraction analysis and transmission electron microscopy. Precipitation at 300 °C for one hour causes formation of the equilibrium β phase. This phase has an f.c.c. structure (a = 2.2 nm), which makes it isomorphous with Mg5Gd. With the prolonged ageing time at 300 °C, the volume fraction of the β phase increases and lattice parameter of the solid solution of α-magnesium decreases.

The electrolytic Zn–Mn coatings were deposited from a sulphate bath with additions of glycine, cysteine, tryptophan or tyrosine as complexing agents. The surface morphology, chemical and phase composition were investigated involving SEM associated with EDX analysis and XRD. The corrosion resistance of obtained Zn–Mn coatings was investigated. The studies of corrosion resistance were carried out in 5% NaCl solution using the potentiodynamic, the electrochemical impedance spectroscopy and the Scanning Kelvin Probe methods. On the basis of the research, the possibility of deposition of Zn–Mn coatings from the galvanic baths with an addition of amine‐derivatives compounds, that is, glycine, cysteine, tryptophan or tyrosine as complexing agents, was demonstrated. It was stated that the kind of the agents in the galvanic bath determine mainly the surface morphology of Zn–Mn deposits. Thus differences in total and local corrosion resistance of the obtained Zn–Mn coatings have been observed. Copyright © 2014 John Wiley & Sons, Ltd.