Effect of Oxygen on High‐temperature Phase Equilibria in Ternary Ti‐Al‐Nb Alloys
Benedikt Distl, Gerhard Dehm, Frank Stein
Abstract
Alloys based on titanium aluminides received a lot of attention because of their capability to substitute Ni‐based superalloys in high‐temperature applications. However, the phase equilibria between the main microstructure constituents (αTi), (βTi), γ (TiAl) and α 2 (Ti 3 Al) can be shifted significantly by impurities such as oxygen especially at high temperatures. This behavior is investigated on the tie‐triangle (αTi) + (βTi) + γ (TiAl) in the ternary Ti‐Al‐Nb system at 1300 °C. An explanation for this behavior could be the occupation of octahedral voids by impurities in certain phases.
Topics & Concepts
Ternary operationMaterials scienceImpurityTitaniumMicrostructureSuperalloyPhase (matter)MetallurgyOxygenOctahedronTitanium alloyThermodynamicsCrystallographyCrystal structureAlloyChemistryComputer scienceProgramming languageOrganic chemistryPhysicsIntermetallics and Advanced Alloy PropertiesMXene and MAX Phase MaterialsSemiconductor materials and interfaces