Electrodeposition of Ni–Mo and Ni–Mo-(nano Al2O3) multilayer coatings. (3rd June 2018)

• Record Type: Journal Article
• Authors: Rezaeiolum, A.; Aliofkhazraei, M.; Karimzadeh, A.; Rouhaghdam, A. S.; Miresmaeili, R.
• Is Part Of: Surface engineering. Volume 34:Number 6(2018)
• Page Start: 423
• Page End: 432
• Publication Date: 2018-06-03
• Subjects: Electrodeposition -- nanoparticle -- multilayer -- corrosion -- wear; Surfaces (Technology) -- Periodicals; Coatings -- Periodicals; 620.4405
• DOI: 10.1080/02670844.2017.1327009
• Languages: English
• ISSNs: 0267-0844

Abstract

ABSTRACT: In the present work, multilayer Ni–Mo–Al2 O3 and Ni–Mo coatings were fabricated on the low-carbon steel using pulse electrodeposition technique from a citrate-ammonia bath. The coatings with different number of layers (32, 128 and 512) were electrodeposited by the periodic alteration of duty cycle (between 20 and 90%) at a constant frequency of 400 Hz and an average current density of 6 A dm −2 . The corrosion resistance of the coatings was estimated using potentiodynamic polarisation and electrochemical impedance techniques and wear properties was also evaluated using pin-on-disk wear test. Potentiodynamic polarisation and electrochemical impedance in 3.5 wt-% NaCl solution showed that 128-layer nanocomposite coatings had the highest corrosion resistance. By increasing the number of the layers in Ni–Mo coatings, their hardness was improved from 563 ± 20 Hv0.1 to 714 ± 42 Hv0.1, while the wear rate was decreased from 9.87 to 5.16 μg N −1 m −1 . The addition of nanoparticles showed favourable impacts on the coatings hardness and wear properties.