Work

Design of an additively manufactured functionally graded material of Ti60-Ti2AlNb with Nb-enriched intermediate layer

Year: 2025

Type: article

Abstract: The graded materials hold great potential for the new generation of aero-engines. Strategic design of compositional transition paths is expected to optimize interfacial bonding characteristics and to mitigate precipitation of detrimental phases in the transition zone, thereby effectively enhancing the comprehensive mechanical performance of graded materials. This study focuses on the fabrication of Ti60-Ti2AlNb graded materials via laser-directed energy deposition (L-DED). Based on thermodynamic calculations, an optimized transition path with Ti2AlNb+Nb intermediate layer is proposed to suppress brittle phase formation and promote strengthening phase precipitation in the transition zone. The feasibility of this transition path was systematically validated by comparing calculated and experimental results. Results indicate that the designed transition path can effectively reduce the fraction of α2 phase and promote the precipitation of O phase by facilitating the transformation of α2 phase to O phase and the precipitation of O phase from B2 phase. The sample with designed path exhibits a room-temperature tensile strength of 1043.3 MPa and an elongation of 6.4%. This study offers a promising approach to regulating the behavior of phase precipitation and optimizing mechanical properties through the design of transition paths, providing a foundation for the industrial application of graded structures.

Source: Journal of Materials Research and Technology

DOI: 10.1016/j.jmrt.2025.11.183