Microstructure, wear and electrochemical behaviors of laser cladding Fe-based coatings with various molybdenum contents

Autor: Qian Li, Qian Wang, Liang Zhang, Dong Xu Chen, Hui Jin, Ji Dong Li, Jun Wei Zhang
Jazyk: angličtina
Rok vydání: 2022
Předmět:
Zdroj: Materials Research Express, Vol 9, Iss 2, p 026504 (2022)
Druh dokumentu: article
ISSN: 2053-1591
DOI: 10.1088/2053-1591/ac4e3d
Popis: Fe-based alloy coatings with different Mo contents were fabricated on 45 steel substrates by laser cladding. X-ray diffractometer (XRD), scanning electron microscope (SEM) and energy dispersive spectrometer (EDS) were used to analyze the phase composition and microstructural evolution of the coatings. The effects of Mo addition on the wear and electrochemical behaviors of the coatings were analyzed by ball-on-disc wear tester and electrochemical workstation. The results showed that the addition of Mo could help refine grains and promote the transition of dendrites to equiaxed grains. With the increase of Mo content, the hard phases changed from Fe _2 B to Mo _2 FeB _2 . Mo and Cr tended to aggregate in the intercrystalline regions in the form of hard phases. When the Mo content was 4.8 wt%, the hardness increased by 3.6 times compared with that of the substrate. The wear resistance of the coatings increased with the Mo addition. Mo played the role of fine grain strengthening and solid solution strengthening, which was beneficial for the improvement of the hardness and wear resistance. Polarization curves and electrochemical impedance spectroscopy test results revealed that the addition of Mo could improve the corrosion resistance of Fe-based coating.
Databáze: Directory of Open Access Journals