Competition between prismatic and basal slip in hexagonal titanium–aluminum alloys with short-range order
P. Kwaśniak, Stéphanie Delannoy, F. Prima, Emmanuel Clouet
Abstract
Plasticity of hexagonal titanium–aluminum alloys depends on the solute concentration and the order state of Al atoms. Development of short-range order (SRO) modifies Al strengthening and impacts the competition between prismatic and basal slip modes. Using ab initio calculations, we study the interaction of a screw dislocation with isolated Al atoms and Al pairs in an hcp Ti existing in short-range ordered Ti–Al alloys. Calculated activation energies reveal pronounced hardening caused by Al addition for both slip systems, which become competitive. This hardening is enhanced for Al pairs, resulting in a reduced plastic anisotropy of Ti–Al alloys with SRO.
Topics & Concepts
Materials scienceAluminiumSlip (aerodynamics)TitaniumAnisotropyHexagonal crystal systemAb initioPlasticityDislocationCrystallographyTitanium alloyHardening (computing)MetallurgyCondensed matter physicsAlloyComposite materialThermodynamicsChemistryOrganic chemistryPhysicsQuantum mechanicsLayer (electronics)Titanium Alloys Microstructure and PropertiesMicrostructure and mechanical propertiesMXene and MAX Phase Materials