Interface Structure and Fracture Energy of Al2O3-Ti Joints

摘要

The behavior and structure of Al2O3-Ti interfaces are important both for directdiffusion bonding and reactive brazing. The good reactivity of titanium with oxide ceramics is well known and there are several industrial applications in which this material couple can be readily used. These results show that various types of interfaces can be produced in Al2O3 to metal systems where the activity of Ti is nearly one. In a liquid state, alumina is in contact with TiAlx intermetallics, either TiAl in infinite and finite couples or Ti3Al in equilibrated couples. The addition of Nb to Ti, leads to the formation of TiAlx(Nb) at the alumina interface. The kinetics of the reaction layer growth and futhermore the structural changes in the interface can be calculated by the experimently derived equations for the infinite and finite couples.