Effect of Cr content on microstructure and oxidation resistance of laser-clad Cu-Ni-Fe-Mo-xCr alloy coating

• Published in: Surface & coatings technology 2020-02, Vol.384, p.125316, Article 125316
• Main Authors: Yang, Yu, Wang, Aihua, Xiong, Dahui, Wang, Zhiwang, Zhou, Dan, Li, Shuangqing, Zhang, Hua
• Format: Article
• Language: English
• Subjects: Chromium; Coatings; Copper; Copper base alloys; Cr content; Cu-Ni-Fe-Mo-xCr alloy; High temperature; Iron; Laser beam cladding; Laser cladding; Medium carbon steels; Microscopy; Microstructure; Molybdenum; Nickel; Optical microscopy; Oxidation; Oxidation resistance; Silicon; Solid phases; Substrates
• ISSN: 0257-8972; 1879-3347
• DOI: 10.1016/j.surfcoat.2019.125316

Cu-Ni-Fe-Mo-xCr type alloy coatings with different Cr content were produced on a medium carbon steel substrate by laser cladding in this investigation. The effect of Cr content on macro-quality, microstructure, phase structure and high temperature oxidation resistance of the coatings was revealed by macro photography, optical microscopy (OM), environmental scanning electron microscopy (ESEM) incorporating with EDX microanalysis, X-ray diffraction (XRD) analysis, respectively. Results showed that, the coatings with Cr content ranging from 0 to and 5 wt% are smooth and crack free while the coatings with Cr content ranging from 7.5 to and 10 wt% are smooth but cracked. The volume content of second phase (Fe,Ni,Si,Cr)2Mo and the high temperature oxidation resistance of the coatings are both increased with an increase in Cr content. •The Cu-Ni-Fe-Mo-xCr alloy coatings with good adhesion to the substrate and pore/crack free were prepared.•Using the liquid phase separation property of alloy to form the second phase.•The addition of Cr improves the content and oxidation resistance of the second phase.