Effect of surfactant on the electrodeposition and wear resistance of Ni–Al2O3 composite coatings

Ni/Al2O3 composite coatings were prepared by direct current (DC), single pulse current (PC) and pulse reversal current (PRC), respectively. The hardness and wear resistance of the coatings were investigated and the morphology and elements distribution in cross-section were analyzed by the application of SEM/EDS, XRF and XRD equipped with stress measuring device. The results show that the hardness of the three kinds of coatings increase with increasing Al2O3 content. The coating prepared by PRC plating exhibits higher hardness and better wear resistance, while that of DC plating has lower hardness and poorer wear resistance. The higher hardness and better wear resistance of coating of PRC plating can be ascribed to fine microstructure and weaker stress between substrate and coatings.

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Mechanical Milling Prepared Nano-Sized Al2O3 Particles Utilized in Electroless Plating Ni-P- Al2O3 Composite Coatings

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.602-604.1700 ◽

2012 ◽

Vol 602-604 ◽

pp. 1700-1705 ◽

Cited By ~ 2

Author(s):

Ai Zhi Yu ◽

Mao Dong Li ◽

Jin Mei Lin ◽

Shu Kuan Zhang

Keyword(s):

Heat Treatment ◽

Particle Size ◽

Wear Resistance ◽

Mechanical Milling ◽

Chemical Method ◽

Composite Coatings ◽

Micro Hardness ◽

Mechanical Method ◽

Al2o3 Composite ◽

Steel Substrates

In this paper, nano-sized Al2O3 particles were prepared by mechanical milling, and Ni-P-Al2O3 composite coatings were plated on Q235 steel substrates, which plating solutions were containing different concentrations Al2O3 particles. The morphology, phase and particle size distribution of the as-prepared Al2O3 particles, and the properties of the coatings were investigated. The results show that, the morphology of the as-prepared Al2O3 particles were spherical and almost size under 100nm, the coatings were uniformly thickness and the Al2O3 particles were uniformly dispersed in the coatings, after heat treatment, the micro-hardness and wear resistance of the coatings were significantly improved, compared with the chemical method prepared Al2O3 particles, the mechanical method prepared Al2O3 particles had the same performance in improving the micro-hardness of the coatings.

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Preparation and wear resistance of pulse electrodeposited Ni–W/Al2O3 composite coatings

Applied Surface Science ◽

10.1016/j.apsusc.2011.01.089 ◽

2011 ◽

Vol 257 (15) ◽

pp. 6340-6346 ◽

Cited By ~ 82

Author(s):

Kung-Hsu Hou ◽

Yann-Cheng Chen

Keyword(s):

Wear Resistance ◽

Composite Coatings ◽

Al2o3 Composite

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Influence of Al2O3 sol concentration on the microstructure and mechanical properties of Cu–Al2O3 composite coatings

International Journal of Modern Physics B ◽

10.1142/s0217979215400214 ◽

2015 ◽

Vol 29 (10n11) ◽

pp. 1540021 ◽

Cited By ~ 1

Author(s):

Xiaojin Wei ◽

Zhendi Yang ◽

Ying Tang ◽

Wei Gao

Keyword(s):

Mechanical Properties ◽

Wear Resistance ◽

Composite Coatings ◽

Nanocomposite Coatings ◽

Wear Volume ◽

Vickers Hardness Number ◽

Microstructure And Mechanical Properties ◽

Al2o3 Composite ◽

Electrical Conducting ◽

Pure Cu

Copper ( Cu ) is widely used as electrical conducting and contacting material. However, Cu is soft and does not have good mechanical properties. In order to improve the hardness and wear resistance of Cu , sol-enhanced Cu – Al 2 O 3 nanocomposite coatings were electroplated by adding a transparent Al oxide ( Al 2 O 3) sol into the traditional electroplating Cu solution. It was found that the microstructure and mechanical properties of the nanocomposite coatings were largely influenced by the Al 2 O 3 sol concentration. The results show that the Al 2 O 3 nanoparticle reinforced the composite coatings, resulting in significantly improved hardness and wear resistance in comparison with the pure Cu coatings. The coating prepared at the sol concentration of 3.93 mol/L had the best microhardness and wear resistance. The microhardness has been improved by ~20% from 145.5 HV (Vickers hardness number) of pure Cu coating to 173.3 HV of Cu – Al 2 O 3 composite coatings. The wear resistance was also improved by ~84%, with the wear volume loss dropped from 3.2 × 10-3 mm3 of Cu coating to 0.52 × 10-3 mm3 of composite coatings. Adding excessive sol to the electrolyte deteriorated the properties.

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