Influence of nickel ion implantation on the inactive braze joining abilities of Al2O3 ceramics

Multi-crystalline Al2O3 ceramics were implanted with 130 keV Ni+ ion beams at 225 °C in a vacuum of 1.33 × 10−3 Pa. The inactive braze joining abilities of the implanted ceramic to 1Cr18Ni9Ti (AISI 321) stainless steel with Ag34Cu16Zn50 (wt%) brazing material were investigated. The relationships between the joining abilities and the surface compressive stresses produced by the ion implantation were studied for the first time. The results showed that when the fluence was less than 5 × 1016 ions/cm2, the surface properties including wetting ability, braze joining ability and produced surface compressive stresses, increased with ion implantation fluence, and reached the maximum value at a point of 5 × 1016 ions/cm2. After this point, the properties decreased upon further increasing the ion implantation fluence.