TY - JOUR

T1 - Formation and evolution of precipitates in an additively manufactured near-α titanium base alloy

AU - Fleißner-Rieger, Christian

AU - Schönmaier, Hannah

AU - Musi, Michael

AU - Stadler, Manfred

AU - Gschiel, Harald

AU - Turk, Christoph

AU - Pfeifer, Tanja

AU - Clemens, Helmut

N1 - Publisher Copyright: © 2022 The Author(s)

PY - 2022/3

Y1 - 2022/3

N2 - Titanium base alloys are frequently used in laser powder bed fusion manufacturing processes and enable the production of lightweight and complex components. This study describes the influence of the heat input and various post-process heat treatments on the martensite formation and its decomposition in an additively manufactured Ti-6Al-2Sn-4Zr-2Mo-Si alloy. The change of the martensite crystal structure from orthorhombic to hexagonal, caused by additional heat input, was proven by high-energy X-ray diffraction. It is shown that the heat input of the laser affects the diffusion of alloying elements such as Mo and Si. This behavior was investigated by atom probe tomography, which confirms clustering of Mo and Si at dislocations and grain boundaries, and allows for linking the heat input during the manufacturing process with the morphology of the observed clusters. Moreover, particular emphasis is laid on explaining the formation mechanism of (Ti,Zr) 6Si 3 silicide particles during a subsequent heat treatment.

AB - Titanium base alloys are frequently used in laser powder bed fusion manufacturing processes and enable the production of lightweight and complex components. This study describes the influence of the heat input and various post-process heat treatments on the martensite formation and its decomposition in an additively manufactured Ti-6Al-2Sn-4Zr-2Mo-Si alloy. The change of the martensite crystal structure from orthorhombic to hexagonal, caused by additional heat input, was proven by high-energy X-ray diffraction. It is shown that the heat input of the laser affects the diffusion of alloying elements such as Mo and Si. This behavior was investigated by atom probe tomography, which confirms clustering of Mo and Si at dislocations and grain boundaries, and allows for linking the heat input during the manufacturing process with the morphology of the observed clusters. Moreover, particular emphasis is laid on explaining the formation mechanism of (Ti,Zr) 6Si 3 silicide particles during a subsequent heat treatment.

UR - http://www.scopus.com/inward/record.url?scp=85124797237&partnerID=8YFLogxK

U2 - 10.1016/j.mtla.2022.101366

DO - 10.1016/j.mtla.2022.101366

M3 - Article

VL - 21.2022

JO - Materialia

JF - Materialia

SN - 2589-1529

IS - March

M1 - 101366

ER -