Abstract:The nanocrystalline Fe-Ni-Cr coatings were electrodeposited by using the pulse current technique. The SEM results showed that the coatings had a mixed morphology of small nodules and fine cauliflower structures at low current densities. Also, the Cr content was increased at expense of Fe and Ni contents at high current densities. XRD patterns confirmed that the pulse current density had a positive effect on the grain refinement. The results of vibrating sample magnetometer (VSM) measurements demonstrated that by increasing the current density, the saturation magnetization was decreased and the coercivity was increased due to the enhancement of Cr content and the reduction of the grain size. The friction coefficient and wear rate values were decreased by increasing the pulse current density. Also, both the adhesive and abrasive wear mechanisms were observed on the worn surfaces. The abrasive grooves and the amount of wear debris were decreased by increasing the pulse current density.

Key words: pulse electrodeposition; current density; nanocrystalline Fe-Ni-Cr coatings; magnetic behavior; tribological properties