A new method for bonding alumina to the alloy titanium-zirconium-molybdenum

Assemblies of TZM alloy with alumina were obtained with a two-step process, much shorter than moly-manganese brazing methods. This new process involves, first, the preoxidation of the alloy in air at 795 °C, followed by hot-pressing in flowing argon, at 1700 °C under 22 MPa. The adherence of the joints, higher than 45 MPa, was explained by two complementary reasons: i) a mechanical contribution, of “tenon and mortise” type and ii) the penetrations of secondary phases (MoO2 and minor phases coming from alumina additives) into both materials that play the role of nails joining the alloy and the ceramics.