A three-dimensional treatment method involving implantation of ions into solids immersed in a high voltage pulse discharge ignited on the left-hand-branch of the Paschen curve was elaborated about fifteen years ago. This method, named 3DII for short, has been used in the equipment JUPITER (Joint Universal Plasma and Ion Technologies Experimental Reactor) for practical purposes. Hereafter, the need for better means to improve the metal surface protection against aggressive media prompted an elaboration of the MOSMET concept which is based on a hybrid treatment involving the processes of implantation and deposition. It is significant that the processes can be set into action simultaneously or separately. In this article, the conditions of hybrid treatment of AISI SAE 1010, 1020 y 1045 carbon steels, their subsequent electrochemical diagnostics and corrosion test results are described. The corrosion rate of the samples treated by titanium hybrid discharge is found approximately an order of magnitude smaller as compared to the non-treated samples.