Open AccessCorrosion behavior of plasma transferred arc and laser cladding Ni-based alloy coatings in different acid solutions
Author(s) -
Cheng Qian,
Haiyan Chen,
Yue Hou,
Fan Li,
Lihua Dong
Publication year - 2019
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/677/2/022068
Subject(s) - materials science , corrosion , scanning electron microscope , x ray photoelectron spectroscopy , coating , metallurgy , alloy , cladding (metalworking) , electrochemistry , polarization (electrochemistry) , composite material , chemical engineering , electrode , chemistry , engineering
The Ni-based coatings were prepared by laser cladding (LC) and plasma transferred arc (PTA) welding, respectively. The corrosion behavior of the coatings were tested by scanning electron microscopy (SEM), X-ray diffraction (XRD), electrochemical corrosion, long-term immersion tests and X-ray photo electron spectroscopy (XPS) analysis. The results of XRD showed that the composite coatings comprised Ni, Cr and Mo. The electrochemical corrosion tests included polarization curves and electrochemical impendance spectroscopy (EIS). The XPS analysis presented samples included Ni, Fe, Cr and Mo oxides, which protected the substrate from corrosion by acid solutions. The results also presented that the Ni-based PTA coating is more resistant to corrosion than the Ni-based LC coating. In the immersion tests, the coatings changed from pitting to general corrosion as the immersion time prolonged.