Study of wear resistance and nanostructure of tertiary Al2O3/Y2O3/CNT pulsed electrodeposited ni-based nanocomposite

Abstract

Electrodeposition of tertiary Alumina/Yitria/carbon nanotube (Al 2 O 3 /Y 2 O 3 /CNT) nanocomposite by using pulsed current has been studied. Coating process has been performed in nickel sulphate bath and nanostructure of the obtained compound layer was examined with high precision figure analysis of SEM nanographs. The effects of process variables, i.e. Y 2 O 3 concentration, treatment time, current density and temperature of electrolyte have been experimentally studied. Statistical methods were used to achieve the minimum wear rate and average size of nanoparticles. Finally the contribution percentage of different effective factors was revealed and confirmation run showed the validity of the obtained results. Also it has been revealed that by changing the size of nanoparticles, wear properties of coatings will change significantly. Atomic force microscopy (AFM) and transmission electron microscope (TEM) analysis have confirmed smooth surface and average size of nanoparticles in the optimal coating. Key words: yitria, electrodeposition, tertiary nanocomposite coatings, wear, carbon nanotube.Nickel and nickel-based alloys are used widely for numerous applications, which most of them require corrosion, wear and heat resistances, including different turbine plants, nuclear power systems, and chemical and oil industries.Ceramic or metal matrix nanocomposite coatings usually have special properties such as dispersion hardening, self-lubricity, high temperature inertness, good wear and corrosion resistance, chemical and biological compatibility [1][2][3][4][5][6][7]. This accounts for the increased application of Ni-based nanocomposites in different industries. In order to meet the requirement for developing novel metal-based nanocomposites, many preparation techniques have been investigated. Considering a technique conducted at a normal pressure and ambient temperature and with low cost and high deposition rate, electrodeposition is considered to be one of the most important techniques for producing nanocomposites and nanocrystals [8][9][10][11].In this paper, tertiary nanocomposite coatings consisting of nanometric-sized Al 2 O 3 /Y 2 O 3 /CNT particles embedded in a Ni-matrix by pulsed electrodeposition method were studied. The nanostructure and wear resistance of obtained nanocomposites were investigated with respect to the different effective factors of coating process. Ni matrix composite coatings containing nano-sized Al 2 O 3 /Y 2 O 3 /CNT fine particles with different average sizes of nanoparticles were prepared in a nickel sulphate bath. The wear performance of these coatings and its relation to the distribution of nanopaticles has been analyzed in a systematical way.The design of experiment (Taguchi method) [12][13] took into account the influencing extent of individual process parameter. This consideration led to the selection of four influential factors, i.e. Y 2 O 3 concentration, time, current density and

Size Effect in Mechanical Properties of Nanostructured Coatings

“…It has been revealed that by changing the size of nanoparticles, wear properties of coatings will change significantly. In the case of average size of nanoparticles ranking of effective factors by their relative contributions is the same as for wear rate which shows strong relation between these two measured properties of coatings [105]. This relation can be seen in Fig.…”

“…The Relation between average size of nanoparticles and wear rates for electrodeposited tertiary nanocomposite layer [105] effects of some process variables have been experimentally studied and statistical methods were used to achieve the minimum wear rate and average size of nanoparticles. It has been revealed that by changing the size of nanoparticles, wear properties of coatings will change significantly.…”

Electrochemical Synthesis of Nanocomposites

“…For nickel matrix electrodeposits, a great variety of particles have been used such as oxides i.e. TiO 2 [41,42], Al 2 O 3 [43], CeO 2 [44,45], ZrO 2 [46], graphene oxide GO [47], carbon nanotubes CNT; Al 2 O 3 /Y 2 O 3 /CNT [48], carbides like SiC [49][50][51], WC [52] and nitrides such as TiN [53] and Si 3 N 4 [54].…”