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In the present work, the results of studies on the structure and corrosion resistance of Al(Co, Ni) layer are shown. The diffusion Al(Co, Ni) layer was created on the cobalt alloy Mar-M-509 substrate by chemical vapor deposition (CVD) method with aluminum trichloride (AlCl3) under the hydrogen atmosphere. The scanning electron microscope (SEM) observations and microtomography measurements of layers were performed. Also an analysis of the chemical (energy-dispersive X-ray spectroscopy (EDS)) and phase (X-ray diffraction (XRD)) composition was carried out. By the X-ray diffraction method (sin2 φ) also the residual stresses were calculated in the matrix of the material. The corrosion resistance was tested with impedance and potentiodynamic methods in 0.1 M Na2SO4, 0.1 M H2SO4 solutions and acidulous 0.1 M NaCl solution (pH = 4.2) at room temperature. The results indicate that the analyzed layer with a thickness of about 14 μm have a similar corrosion resistance compared to the base material - Mar-M-509® cobalt alloy. Only in the strongly acidic environments, the corrosion resistance of the layer is remarkably decreased. [ABSTRACT FROM AUTHOR]

In the present work, the results of studies on the structure and corrosion resistance of Al(Co, Ni) layer are shown. The diffusion Al(Co, Ni) layer was created on the cobalt alloy Mar-M-509 substrate by chemical vapor deposition (CVD) method with aluminum trichloride (AlCl3) under the hydrogen atmosphere. The scanning electron microscope (SEM) observations and microtomography measurements of layers were performed. Also an analysis of the chemical (energy-dispersive X-ray spectroscopy (EDS)) and phase (X-ray diffraction (XRD)) composition was carried out. By the X-ray diffraction method (sin2 φ) also the residual stresses were calculated in the matrix of the material. The corrosion resistance was tested with impedance and potentiodynamic methods in 0.1 M Na2SO4, 0.1 M H2SO4 solutions and acidulous 0.1 M NaCl solution (pH = 4.2) at room temperature. The results indicate that the analyzed layer with a thickness of about 14 μm have a similar corrosion resistance compared to the base material - Mar-M-509® cobalt alloy. Only in the strongly acidic environments, the corrosion resistance of the layer is remarkably decreased. [ABSTRACT FROM AUTHOR]

The paper presents the results of examinations of the structure and properties of Al2O3 + Ni3Al + Ni(Cr, Fe, Al) + Cr-Ni + Cr7C3 multilayers produced on nickel alloys by the plasma assisted chemical vapour deposition method with the participation of trimethylaluminum vapours in gaseous atmosphere. The layers have a high surface hardness of about 1200HV0.05, and high heat and frictional wear resistance. In order to find a correlation between the structure of the multilayers and their properties, the following examinations have been executed: phase analysis by XRD and surface analysis by XPS, analysis of microstructure by optical and scanning electron microscopes as well as X-ray microanalyser, micro-hardness measurements, corrosion and frictional wear resistance testing. [ABSTRACT FROM AUTHOR]