versión On-line ISSN 0718-0764
HOYOS, Bibian A; MARTINEZ, Luisa F y SALAZAR, Álvaro F. Electroplating of Hard Nickel With Triangular Pulse Current Waveforms. Inf. tecnol. [online]. 2007, vol.18, n.4, pp.9-14. ISSN 0718-0764. http://dx.doi.org/10.4067/S0718-07642007000400003.
In this paper it is studied the frequency and current density effect on hardness of nickel electroplating obtained by means of triangular and rectangular pulse current and their comparison with those obtained using direct current. Hardness measurements were done following the ASTM E384 standards. Morphologic qualitative description of deposits was done using a Scanning Electronic Microcopy (SEM) according with the ASTM E112, E3 and E93 standards. The experimental results showed that at 4 A/dm2 the hardness of deposits is affected by the current waveform, producing hardness in the order: ramp-down > rectangular > ramp-up. For the experimental conditions explored here, the highest value of hardness was obtained at t 20 A/dm2 and 60 Hz. For this current waveform the hardness value diminishes when the duty cycle increases. The hardness increases up to 300% when using pulse current instead on direct current.
Palabras clave : pulse current; nickel electroplating; hardness; triangular waves.