Corrosion of galvanic couplings of Ni-Cr and Co-Cr alloys with Ti-6Al-4V in artificial saliva using electrochemical methods

Resumo

In this work, the open-circuit corrosion potentials of the alloys studied in aerated artificial saliva were determined; in the same solution, the potentiodynamic polarization curves of said alloys have been drawn. The corrosion potentials and current intensities of the galvanic coupling of the Ti-6Al-4V alloy with the Co-Cr and Ni-Cr alloys were determined using the Evans method, finding that the galvanic couples more resistant to corrosion in the electrolytic medium considered are those formed between the Ti alloy and the Co-Cr alloys; the least resistant are those formed between Ti alloy and Ni-Cr alloys. The corroded surfaces of the seven alloys considered in this work were also studied, and by EDAX the corrosion products due to the ions detached in the electrolytic medium were analyzed. Keywords: Galvanic couplings, dental alloys, Co-Cr, Ni-Cr, corrosion.