Polarization of jewelry gold alloys by bipolar current pulses in a polishing electrolyte

Abstract

The polarization is examined of 585th hallmark (14 karat) standard jewelry gold alloys of different colors (red, European yellow, and white) using bipolar current pulses with different amplitude-time parameters aimed at optimizing the electrochemical polishing modes.

Technological features of electrochemical polishing of gold alloys by pulse currents

“…The investigation shows that the polarization peak magnitudes connected with the anode dissolution are not achieved immediately. The dynamics of their evolution are different in the micro-and millisecond time ranges [5]. Thus, by varying the amplitude and current pulse duration in this time range, it is possible to form an anode potential ensuring a compromise between the rates of dissolution and the passivation processes.…”

Principles of the express method for controlling interelectrode space condition during wire electrochemical processing

“…A similar approach was used in [8], using a complex mathematical apparatus not suitable for operative quantitative analysis of response oscillograms. In the subsequent work [9] only a qualitative analysis of oscillograms was conducted.…”

“…parameters RE, RF, C of the electrical equivalent substitution scheme of an electrochemical cell. Polarization growth area (Figure 5b) was approximated by the least squares method using function (9), which is a response function when passing the front edge of current pulse through an electrochemical cell. The decrease of area which corresponds to the back edge of the switch-off of current pulse, was approximated by the function represented in the second term Eq.…”