Electrodeposition of nanocrystalline Ni–W coatings strengthened by ultrafine alumina particles

Ni–W/ZrO2 nanocomposites obtained by ultrasonic DC electrodeposition

“…As shown previously for the Ni-W/Al 2 O 3 composite system, shape and phase compositions of nanoparticles are crucial parameters affecting the content and uniform distribution of ceramic particles much more than their size in the nanometer range (<100 nm). It was established that in contrast to the multiphase Al 2 O 3 nanoparticles of irregular crystallites, the monophasic aAl 2 O 3 of spherical shape embedded much more easily and more uniformly in the nanocrystalline Ni-W alloy matrix, resulting in an increase of composite ceramic fraction (even 10 times) and a substantial increase in hardness [14].…”

“…Thus, it would be expected that the incorporation of zirconium oxide as ceramic hard particles into Ni-W alloy matrix allows composites of outstanding characteristics to be obtained, taking into account the properties of both components and their nanocrystalline microstructure. Moreover, the results of our previous study on electrodeposition and characterization of Ni/Al 2 O 3 and Ni-W/Al 2 O 3 composites showed a significant improvement of the microhardness and wear resistance as compared to the pure nickel coatings [14,23,24].…”

“…In contrast, the decrease of the ZrO 2 content incorporated in the coatings deposited under the higher US frequency studied (130 kHz) has been observed. The effect could be compared to excessive bath agitation, which causes the loosely adsorbed nanoparticles to be removed from the cathode surface before they are co-deposited [14,24,37,38]. Thus, in further experiments the frequency of 35 kHz was accepted as the most favourable for sufficient nanoparticle incorporation.…”

“…Recently, it was found that the incorporation of different ceramic particles (e.g., Al 2 O 3 , TiO 2 , SiC, WC, CeO 2 , etc.) into Ni-W deposits can improve the tribological and micromechanical properties of the resulting composites [14][15][16][17][18]. However, composite coatings of a nanostructured Ni-W matrix reinforced by zirconia (ZrO 2 ) nanoparticles are new materials, although the possibility of fabrication Ni-W/ZrO 2 coatings by electrochemical methods has been presented in a recently published paper [19].…”

Ni-W Electrodeposited Coatings on Low Carbon Steel Substrate: Fatigue Observations

“…The Ni-W coatings were electrochemically deposited using a well-established process ( Ref 8,22,23) ) DC powered by a PAR273A potentiostat/galvanostat were used as a cathode. Prior to each experiment, the steel substrates were degreased, mechanically and chemically polished (in a solution of hydrogen peroxide and oxalic acid at 35°C), and then rinsed in distilled water in ultrasounds.…”