Deformation-free geometric recrystallisation in a metastable β-Ti alloy produced by selective laser melting
Ahmad Zafari, Edward W. Lui, Kenong Xia
Abstract
Super-transus heat treatments conducted on an additively manufactured body-centred-cubic β-Ti alloy led to the formation of equiaxed β grains from an initially columnar structure. The grain structure was transformed thanks to a combination of Plateau-Rayleigh instability and grain growth driven by reduction in grain boundary surface area. This is a new type of geometric recrystallisation with no deformation involved. Other mechanisms proposed based on either deformation-induced recrystallisation or martensitic decomposition are dismissed owing to low dislocation density and absence of martensitic transformation in the alloy studied.
Topics & Concepts
Materials scienceEquiaxed crystalsAlloyDiffusionless transformationDeformation (meteorology)MetastabilityMetallurgyGrain boundaryDislocationMartensiteRecrystallization (geology)Grain growthSevere plastic deformationTitanium alloyGrain sizeMicrostructureComposite materialPaleontologyBiologyQuantum mechanicsPhysicsAdditive Manufacturing Materials and ProcessesTitanium Alloys Microstructure and PropertiesHigh Entropy Alloys Studies