Joining of alumina ceramics with Ti and Zr interlayers by spark plasma sintering

•In this study, alumina ceramics were joined by Spark Plasma Sintering (SPS) technology with titanium and zirconium metals applied as interlayers. In the current state of art, titanium successfully joined alumina by SPS for the first time, while bonding with zirconium was not previously mentioned in the literature.•Titanium joined with alumina at 700, 800, and 900 °C (force 3 kN), however, the bond from 800 °C stands out with the highest integrity and stability among others. The formation of oxides and metallic compounds are the expected result of the SPS treatment.•Zirconium-alumina bonding was achieved at 800, and 900 °C (force 4.2 kN). The higher temperature resulted in the better quality of bonding, but worse than the titanium systems. The ZrO2 formation could decrease the stability in the joined system.