Al-based functionally graded super-intermetallic compounds for the turbine blade of a high-performance jet engine

Area of Science:

• Materials Science and Engineering
• Additive Manufacturing
• Metallurgy

Background:

• Functionally graded materials (FGMs) offer tailored properties for demanding applications.
• Aluminum-Titanium-Vanadium (Al-Ti-V) alloys are critical for high-temperature structural components.
• Advanced manufacturing techniques are essential for creating complex material gradients.

Purpose of the Study:

• To fabricate a discrete Al-based functionally graded structure with a specific Al-Ti-V composition gradient.
• To investigate the microstructural characteristics and mechanical properties of the fabricated FGM.
• To evaluate the potential application of this FGM in high-performance jet engine turbine blades.

Main Methods:

• Fabrication of the Al-based FGM using a dual-hybrid approach: laser powder bed fusion (L-PBF) and directed energy deposition (DED) with CNC milling.
• Characterization of the material's composition, microstructure, and tensile strength.
• Topological optimization of a turbine blade system utilizing the FGM properties.

Main Results:

• Successful fabrication of an Al-based FGM with a discrete compositional gradient (48.1Al47.9Ti4.0V/73.7Al24.2Ti2.1V/89.5Al10.0T0.5V).
• Achieved high tensile strength ranging from 0.5 to 1.7 GPa, attributed to rapid solidification, specific intermetallic phases (γ-like matrix, γ'-like precipitates), and V-based compounds at grain boundaries.
• Identified large, anisotropically lamellar precipitate phases in dendritic regions.
• Demonstrated low densities (2.9-3.7 g cm⁻³) and high thermal resistance (450-900 °C).

Conclusions:

• The developed Al-based FGM exhibits exceptional tensile strength and thermal properties.
• The unique microstructure, including intermetallic phases and grain boundary precipitates, is key to its enhanced mechanical performance.
• The FGM is suitable for topological optimization in high-performance jet engine turbine blades, enhancing structural stiffness and performance.