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In this study, Ni–C films have been fabricated via pulse electrochemical deposition and carbon sol reinforcement methods. The surfacing of prepared films significantly improved due to the uniform distribution of nanoparticles. Additionally, the maximum thickness is attained when the concentration of carbon sol is 15ml/L. X-ray diffraction analysis of the Ni–C composite films reveals adding carbon sol effectively refines the grain size of prepared films. The highest film hardness, 420HV, is achieved at a carbon sol concentration of 15ml/L, corresponding to the best wear and corrosion resistance. Excessive carbon sol can lead to agglomeration of carbon particles, resulting in defects such as cracks and pores within the coating, thereby degrading its performance.

Nano-composite Ni-Al₂O₃ coatings due to their good wear and corrosion resistance have been widely used in different industries. The agglomeration of nano-particle ceramics in the electrolyte is a serious problem in electrodeposition process that leads to the presence of agglomerated particles in the coating and influences its properties. Using a suitable surfactant can be helpful to control the agglomeration of ceramic particles. In this research nano-composite Ni-Al₂O₃ coating has been deposited from an alumina containing Watts bath using a square pulse current and Sodium Dodecyl-Sulphate (SDS) as surfactant. It was observed that SDS addition has an important effect on the reduction of particles agglomeration and increases the incorporation of finer particles into the coating. Addition of saccharin to the electrolyte, decreases the grain size and the alumina content in the coating, and also, leads to lower agglomeration and better distribution of ceramic particles. Moreover, the synergistic addition of SDS and saccharin, decreases the grain size, increases the hardness and wear resistance, but has no effect on the crystallographic texture of the coating.

Zn and Zn–Bi coatings were electroplated on mild steel substrate by direct and pulse current (PC) techniques. The effects of Bi and deposition method on the phase, microstructure and mechanical properties of Zn-based coatings have been studied. Results showed that the crystal orientation and microstructure of Zn–Bi coatings were different compared to the pure Zn coating. By adding a small amount of Bi solution into Zn electrolyte, the microhardness of Zn–Bi coatings was increased by two times, and the wear volume loss was also decreased. Finer grain size and smoother surface can be achieved by utilizing PC deposition, resulting in better mechanical properties compared to the direct current (DC) deposition.

This study applied the pulse electrodeposition and duplex electrodeposition techniques to improve the mechanical properties of Cu–Sn–Zn–TiO₂ nanocomposite coatings. The phase constituents and surface morphologies of prepared coatings were characterized. The cross-sectional information was recorded. The mechanical properties were determined by microhardness and wear tests. All the prepared coatings presented a nodular surface. Both the addition of TiO₂ particles and nickel inner layer refined the coating surface. The pulse electrodeposition led to increased microhardness, while the addition of nickel inner layer further increased the mechanical performance. The best mechanical performance was achieved for the duplex Cu–Sn–Zn–TiO₂/Ni nanocomposite coating prepared via pulse electrodeposition.

Square-wave cathodic current modulation was used to electrodeposit fine-grained iron from citric acid bath. The effect of pulse on-time, off-time, peak current density, and total plating time on the grain size, surface morphology, and crystal orientation was determined. X-ray diffraction analysis and modified Williamson–Hall relation were used to determine the average grains size of the coatings. The experimental results showed that an increase in peak current density resulted in considerable refinement in crystal size of the deposits. An increase in the pulse off-time at constant on-time and peak current density resulted in a progressive increase in crystal size. However, the crystal orientation remained unaffected with increasing off-time. The design of the pulse deposition parameters is described in terms of the transport limitations through the diffusion layer and electrochemical interface stability.