Effect of magnetic field on electroplating Ni/nano-Al2O3 composite coating

The influence of static horizontal magnetic field on the electrocodeposition process of Ni/nano-Al2O3 composite coating has been studied in a modified Watts electrolyte through stationary and dynamic electrochemical investigations. The results showed that the mass transport process and charge transfer process were enhanced by applying magnetic field. The results of SEM and XRD showed that the nickel grains were refined by adding nano-particles and (2 2 0) crystal orientation was strengthened by increasing magnetic flux density (MFD). Alumina particles content and deposit rate increased with increasing MFD due to the magneto hydrodynamic effect (MHD effect). However, the current efficiency decreased with particle content increased.