Microstructure and properties of Ta-reinforced NiCuBSi + WC composite coating deposited on 5Cr5MoSiV1 steel substrate by laser cladding

Ni-based alloy cladding layers with different graphene sheet additions were prepared by laser cladding on the 40CrNi2Si2MoV steel substrate. The influence of the graphene sheet on the microstructure and properties of the cladding layers was investigated. The results show that owing to the diffusion-reaction dissolution, the graphene sheet addition does not bring a corresponding change in the phase constitutions of the cladding layers, i. e., the cladding layers are still composed of γ-Ni, Ni3B, and M7C3 phases. But what has changed is that the solidified structure is refined, and the volume fractions of the eutectic and the carbide are increased with the increase of graphene sheet addition. As a result, the hardness and the wear resistance of the cladding layers gradually increase, whereas the friction coefficient firstly decreases and then increases, with the lowest friction coefficient obtained at 0.5 vol.% graphene sheet addition. Compared to the Ni-based alloy cladding layers with micro-size graphite additions, the studied cladding layers exhibit improved hardness and wear resistance, good forming quality, and increased friction coefficient. DOI: http://dx.doi.org/10.5755/j01.ms.25.3.19173

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Microstructure and Properties of Brush Electroplated Nano-SiC-Al2O3/Ni Composite Coating

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.373-374.285 ◽

2008 ◽

Vol 373-374 ◽

pp. 285-288 ◽

Cited By ~ 4

Author(s):

Hua Yang ◽

Shi Yun Dong ◽

Bin Shi Xu

Keyword(s):

Zeta Potential ◽

Composite Coating ◽

Nickel Coating ◽

Steel Substrate ◽

Pure Nickel ◽

Nano Particles ◽

Strengthening Effect ◽

Microstructure And Properties ◽

1045 Steel ◽

Sic Particle

This paper investigated the effect of nano-SiC particle on microstructure and properties of brush electroplated nano-Al2O3/Ni composite coating. Three kinds of coatings, such as pure nickel coating, nano-Al2O3/Ni composite coating and nano-SiC-Al2O3/Ni composite coating, were fabricated on 1045 steel substrate. Before deposited, Zeta potential of nano-particles in the solution was examined. The results show Zeta potential of the nanoparticles in the nano-Al2O3/Ni electrolyte is negative, but that of the nanoparticles in nano-SiC-Al2O3/Ni electrolyte is positive when the pH value of electrolyte is about 7.5. Energy dispersive spectroscopy (EDS) results show Al element content in the nano-Al2O3/Ni coating is 5.65%, while the content of Al and Si elements in nano-SiC-Al2O3/Ni coating is 5.63% and 4.86% respectively. It confirms that nano-SiC particle co-deposited in the composite coating while nano-Al2O3 particle content keeps constant. The microhardness of nano-SiC-Al2O3/Ni coating exhibits the highest, while the pure nickel coating is the lowest. And surface morphology of nano-SiC-Al2O3/Ni coating is the most smooth and compact among the three coatings. The wear test results reveal that wear resistance of nano-SiC-Al2O3/Ni coating is 1.7 times of that of nano-Al2O3/Ni coating, and 2.3 times of that of pure nickel coating. The above results show the nano-SiC particle services a strengthening effect on the combination performance of nano-SiC-Al2O3/Ni coating.

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