The paper reviews some recent results on electron beam treatments of metallic bilayers. Sheets of AISI 316 austenitic stainless steel were mechanically clamped on a substrate of C40 plain carbon steel. The microstructure of the irradiated surfaces was characterized by light and scanning electron microscopy, X-ray diffraction and Mossbauer spectroscopy. The experimental procedure allowed to obtain a variety of surface steels whose chemical composition ranges from that of the original stainless steel (cladding) to that of steels with lower Ni/Cr contents (alloying). Austenitic and ferritic-martensitic microstructures were accordingly obtained. Electrochemical corrosion tests were carried out on the irradiated samples. The results show that the corrosion behaviour of the cladded or alloyed substrate is consistent with that of the untreated AISI 316 stainless steel or with that of steels having a similar Ni/Cr content.