A study of surface finishing in pulse current electroforming of nickel by utilizing different shaped waveforms

This paper studies experimentally and theoretically the effect of different types of shaped waveform on the surface finish of nickel electroforms in pulse current electroforming. Experimental results show that the quality of the electroforms, in terms of surface roughness improvement, influenced by the types of waveform is of the order of ramp and triangular both with relaxation time>rectangular>ramp and triangular sawtooth. The results show that at the same cathodic peak current density, pulse period, and a fixed electrodeposition time or electrodeposition thickness, the surface roughness can be reduced by as much as two to three times when a relaxation time was used in the cases of ramp and triangular waveforms. These results are supported by the theoretical predictions and the study of the surface morphology of the electroforms by scanning electron microscopy.