Surface and Cross-Sectional Characteristics and Electrochemical Corrosion Behaviour of Laser Thermal Sprayed Amorphous Al-Ni-Fe-Gd Coatings
B-X. Yan and D-J. Kong
Amorphous Al80Ni10Fe5.5Gd4.5, Al70Ni20Fe5.5Gd4.5 and Al60Ni30Fe5.5Gd4.5 coatings were fabricated on S355 structural steel using a laser thermal spraying (LTS). The microstructure, chemical elements and phase composition of obtained coatings were analyzed using a scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and X–ray diffractometer (XRD), respectively. The effects of powder composition on the amorphous forming capability were subsequently discussed. The electrochemical corrosion properties of Al–Ni–Fe–Gd coatings with the different composition were analyzed using an electrochemical workstation. The corrosion potential of Al–Ni–Fe–Gd coatings with the Al and Gd ratios of 80:4.5, 70:4.5 and 60:4.5 is -1.21, -1.05, and -0.59 V, respectively, showing that the corrosion potential shift positively with the Al and Gd ratios increasing, which improve their electrochemical corrosion resistance.
Keywords: Laser thermal spraying (LTS), S355 structural steel, amorphous Al–Ni–Fe–Gd coating, composition ratio, microstructure, phase, electrochemical corrosion