Effects of Cladding Speed on the Tribo-Corrosive and Electrochemical Performance of a Laser Clad FeCoCr-50%Al Coating on S355 Structural Steel
W-C Wang, C Wu and D-J Kong
FeCoCr–50%Al coatings were clad with a high power diode laser (HPDL) on to the surface of S355 structural steel at the different cladding speeds. The effects of laser cladding speed on the tribo-corrosive in 3.5% NaCl solution were analysed using a ball-on-disc wear tester and the electrochemical performance was investigated using an electrochemical workstation. The results show that the average coefficient of frictions (COFs) of the laser clad FeCoCr-50%Al coatings fabricated with laser cladding speeds of 3, 5 and 7 mm/s were 0.586, 0.704, and 0.763, respectively; and the corresponding wear rates were 0.363, 1.015 and 0.454 mm3/Nm, respectively. The wear mechanisms were found to be adhesion wear, abrasive wear and corrosion wear. The polarization curves of the laser clad FeCoCr-50%Al coatings shifted positively than the S355 structural steel substrate. The electrochemical resistance of the laser clad FeCoCr-50%Al coating deposited at the laser cladding speed of 7 mm/s was the highest of the three speeds studied.
Keywords: High power diode laser (HPDL), FeCoCr-50%Al coating, S355 structural steel, laser cladding, speed, coefficient of friction (COF), tribocorrosive, wear mechanism, electrochemical corrosion