Assessment of Tribological behavior of nickel-nano Si₃N₄ composite coatings fabricated by pulsed electroplating process

Abstract

Pure nickel and nano-composite nickel-silicon nitride (Si 3 N 4) coatings were fabricated using pulsed current electrodeposition technique. A control sample for each coating was created and the effect of current density, duty cycle, and pulse frequency on the tribological properties of the electrodeposited coatings was investigated by altering these parameters. X-ray diffraction, scanning electron microscopy and pin-on-disk tests were performed to assess the properties of the fabricated coatings. X-ray diffraction results indicated that both pure and nano-composite coatings possess preferential growth of (111) crystallite planes, which results in the formation of binary symmetrical shaped grains. However, incorporating particles into the coating hindered the growth on other planes, specially (200) growth plane. Incorporation of Si 3 N 4 particles into the coating reduced crystallite size and increased grain refinement; both of which resulted in the increased microhardness of the deposited coatings through dispersion strengthening mechanism. Complementary atomic force microscopy investigations indicated that the roughness of all nano-composite samples was higher than that for the pure nickel coating. After incorporation of Si 3 N 4 particles the wear behavior of all coatings was improved as a result of the improved hardness. Measured wear rates indicate that increasing the current density, during electrodeposition, is the most influencing parameter in reducing the wear coefficient. Furthermore, implementing particles changes the wear mechanism from high plastic deformation, gouging, and delamination to ploughing. Although nano-composite coatings exhibit wider grooves on the surface compared to those on pure nickel coatings, they tend to adhere better to the substrate. The friction coefficient for all nano-composite coatings were marginally higher than that for pure nickel coating, to our understanding, as a result of inadequate load carrying effect of silicon nitride particles.

Friction and wear performances of Si3N4 ceramic matrix composites: A review from the perspectives of doped phase, layered structure design, and laser surface texturing

“…104 Furthermore, metal-Si 3 N 4 composite coatings are also commonly used as wear-resistant films. [105][106][107]…”

“…It was concluded that gas lubrication was similar to water lubrication which was often used to adjust friction performance 104 . Furthermore, metal–Si 3 N 4 composite coatings are also commonly used as wear‐resistant films 105–107 …”

Tribological behavior and wear mechanism of Cu/CF/phenolic resin sandwich composites under current

“…The higher the bond strength between resin and fiber was, the better the mechanical properties of composite. In addition, it is beneficial to the conduction of friction heat and the transfer of internal stress, effectively reducing the wear rate of the contact zone [25]. The ILSS cross-section of phenolic resin contact strip in Figure 7(c) was serrated on the interface between CF and phenolic resin, indicating a high toughness of the interface.…”

Effect of Current on the Characteristics of CuNi-G Nanocomposite Coatings Developed by DC, PC and PRC Electrodeposition

“…18,19 Pulse current (PC) and pulse reverse current (PRC) electrodeposition techniques have recently attracted many researchers for the synthesis of composite coatings in comparison to the conventional DC electrodeposition techniques. 20 In PC and PRC electrodeposition techniques, the adjustment of the applied potential, duty cycle, cathodic/anodic pulses, and pulse waveform can alter the surface morphology, elemental composition, and microstructure of the resulting composite coatings. 21 The charging and discharging of the electric double layer around the cathode occur due to the periodic alteration of the current between zero to positive values in the PC mode, and from positive to negative values in the PRC mode.…”