Electroless deposition of ternary Ni–P alloy coatings containing tungsten or nano-scattered alumina composite on steel

Abstract

The performance of ternary electroless deposited Ni-P-W and Ni-P-alumina composite coatings on low carbon steel substrates was studied. The effect of experimental parameters, such as temperature, pH, nickel sulfate concentration, sodium hypophosphite concentration, sodium citrate concentration, and deposition time on the deposition rate were investigated. The coating brightness, coherence, and uniform surface distribution were improved due to addition of W and alumina. The coating performance was evaluated based on the wear-resistance, micro-hardness, and corrosion resistance. The Ni-P-W ternary alloy coatings showed the highest micro hardness, wear-resistance, brightness, and corrosion resistance. The improvement in the performance of Ni-P-W coatings can be explained by the formation of a tungsten phosphide phase.

EFFECT OF TiO2PARTICLES ON MICRO-HARDNESS, CORROSION, WEAR AND FRICTION OF Ni–P–TiO2COMPOSITE COATINGS AT DIFFERENT ANNEALING TEMPERATURES

“…At 600 C, the hardness and wear resistance of Ni-W-P coatings is decreased. Hamdy et al 33 have observed that the weight loss due to wear is decreased with increase in incorporation rate of alumina particles in the coating. From Fig.…”

Effect of specimen orientation and heat treatment on electroless Ni-PTFE-MoS2 composite coatings

“…1,2 Co-deposition of solid lubricants such as polytetrafluoroethylene (PTFE), [3][4][5] MoS 2 , 6-8 graphite, 9 and carbon nanotubes 10,11 into the EN coating improves its tribological properties by reducing friction coefficient. Although PTFE provides a very low friction coefficient, EN-PTFE composite coatings are not expected to be useful in heavy-duty applications because PTFE is a soft polymer and does not have a layered structure like graphite.…”

The rate of electroless deposition of a four-component Ni–W–P–ZrO2 composite coating from a glycine bath

“…Tungsten, being a metal with a high melting point, improves the high temperature resistance of coatings based on nickel. The three-component tungsten-containing nickel coatings described in the literature are characterized by good mechanical properties and elevated corrosion resistance [10,12,18,19,41]. Zirconium(IV) oxide is a very hard (9 on Mohs scale of hardness) powder resistant to aggressive chemical compounds.…”