Study on Corrosion Resistance of Electrodeposited RE-Ni-W-P-SiC Composite Coating

摘要

Corrosion resistance of RE-Ni-W-P-SiC composite coating and 316L stainless steel in corrosion media of H_2SO_4, HCl, H_3PO_4 and FeCl_3 solutions at different concentrations by means of immersion methods and anodic polarization curves obtained by DHZ-l1 electrochemical synthetic tester and HDV-7 transistor constant potentiometer Immersion experiment results show that corrosion rate of RE-Ni-W-P-SiC composite coating as-deposited in HCl solutions increases with the rise of HCl concentrations, on the contrary, the corrosion rate of the composite coating after heat treatment decreases with increasing the HCl concentrations. the corrosion rates of the coatings as-deposited and after heat treatment in H_2SO_4 and H_3PO_4 solutions respectively decrease with the rise of H_2SO_4 and H_3PO_4 concentrations. the corrosion rate of the deposit as-deposited in FeCl_3 solutions decreases with increasing FeCl_3 concentrations, while the rate of the composite coating after heat treatment increases with the rise of FeCl_3 concentrations. In addition, the corrosion rate of 316L stainless steel in the corrosion media of H_2SO_4, HCl, H_3PO_4 and FeCl_3 solutions at different concentrations increases with rising of concentrations. Furthermore, the corrosion rate of 316L stainless steel in the corrosion media of H_2SO_4, HCl, H_3PO_4 and FeCl_3 solutions respectively is much greater than that of the RE-Ni-W-P-SiC composite coating as-deposited and after heat treatment in the same corrosion media.