Application of ion implantation to ceramic/metal joining

The joining of ceramics to metals is problematic primarily due to the vastly different atomic bonding in these materials. In an attempt to overcome this problem MEVVA ion implantation of titanium into alumina was performed to modify the atomic bonding in the near-surface region of the ceramic. The brazing of alumina to copper, before and after implantation, was performed using both reactive and non-reactive Cu-Ag eutectic brazes. It has been established, for the first time, that metallic implantation of ceramic enables joining to metal with non-reactive braze. Extensive characterisation of faying surfaces was carried out by Rutherford backscattering (RES), glancing angle X-ray diffraction (GAXRD), four-point probe conductivity tests, and braze wettability tests. It has been demonstrated that implantation drastically changes the nature of bonding in alumina by forming metallic-like compounds such as TiO2 thus enhancing the degree of wetting by braze compared to the unimplanted alumina.