Five Ni-Cr industrial dental alloys, containing or not containing beryllium, have been studied by cyclic voltammetry andin situ Raman spectroscopy, in electrolytic solutions with or without chloride. In the absence of chloride, the five samples behave similarly, but in KCl solution, localized corrosion appearing as “black dots” is particularly evident in the case of the Be-containing alloys. Raman spectroscopy allows the identification of these local corrosion products as different forms of molybdates and chromates, together with some other unidentified compounds.