Behaviour of MEVVA metal ion implantation for surface modification of materials

MEVVA ion implantation of Mo, Mo + C and Ti + C in H13 steel at high ion flux was studied. The results show that dispersive hardening phases grow with increasing ion flux. The growth of the phases is accelerated by annealing. The resistance to wear and corrosion for Mo-implanted steel is improved relative to unimplanted steel. After corrosion, the dispersive hardening phases which inhibit corrosion can be observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). A dense network of phases for Mo + C-implanted steel is observed by SEM and TEM. The corrosion resistance of Mo + C-implanted H13 steel is much better than that of Mo-implanted H13 steel. The corrosion current density for Ti + C-implanted H13 steel is very small (0.1 mA cm −2 ); after annealing, the current density is near zero. SEM observation shows that, after corrosion for 50 voltage loops, no corrosion trace can be observed.