Properties of Ti-6Al-4V Lattice Structures with In-Situ Alloying and Functional Gradient

Authors

DOI:

https://doi.org/10.20535/2521-1943.2025.9.4(107).339736

Keywords:

lattice structures, Ti-6Al-4V, SLM, LPBF, in-situ alloying, functionally graded materials, mechanical properties, elastic modulus, strength, anisotropy

Abstract

Problem statement. The object of research is lattice structures made of Ti-6Al-4V titanium alloys, manufactured using selective laser melting (SLM) and laser powder bed fusion (LPBF), including in-situ alloyed and functionally graded variants. The problem lies in the lack of systematized data on the relationship between process parameters of additive manufacturing, the resulting microstructure, and mechanical properties, which limits the application of such materials in aerospace industry. Purpose of the study. To determine the influence of in-situ alloying and functional gradient lattice structures on the formation of microstructure, elastic modulus, strength, and energy absorption capacity of Ti-6Al-4V produced by SLM/LPBF. Methodology. Experimental specimens of Ti-6Al-4V–3 % Cr were fabricated by SLM/LPBF under controlled energy density and scanning parameters. The structure was analyzed using X-ray diffraction (XRD), electron microscopy (SEM, EBSD, EDS), and lattice geometry evaluation. In parallel, finite element modelling (FEM) was applied to predict mechanical behavior. Results. The results demonstrate that in-situ alloying with Cr stabilizes the b-phase and controls the distribution of a + b microstructure, thereby increasing alloy strength and stiffness (UTS up to 1050 MPa, elongation 8–10 %). Lattice structures of elliptical and spiral geometry exhibited maximum elastic moduli of 0.76 GPa and 0.41 GPa respectively, while reducing structural mass. Functionally graded lattices with variable strut diameter (1–1.2 mm) ensured more efficient stress transfer and controlled local stiffness. The effect is attributed to substrate preparation and cyclic heating during LPBF, which promoted a¢ martensite decomposition, b-phase stabilization, and stress reduction in critical regions. Conclusions. The novelty of the study lies in the combination of in-situ alloying and functional geometry gradient, which enables achieving an optimal strength-to-weight ratio, improving energy absorption, and providing controlled mechanical response throughout the component volume. Potential applications cover aerospace engineering, where weight reduction under high stiffness and strength is crucial, as well as structural elements with increased resistance to local loading.

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Published

2025-12-29

How to Cite

[1]
S. Kyrylakha, “Properties of Ti-6Al-4V Lattice Structures with In-Situ Alloying and Functional Gradient”, Mech. Adv. Technol., vol. 9, no. 4(107), pp. 469–482, Dec. 2025.

Issue

Vol. 9 No. 4(107) (2025)

Section

Aviation Systems and Technologies

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Copyright (c) 2025 Світлана Кирилаха

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