BLT-Ti₂AlNb: A New Milestone in Additive Manufacturing Powders

25 7月
2024
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Ti2AINb alloy is emerging as one of the most promising high-temperature, lightweight structural materials due to its superior properties, including excellent room temperature ductility, fracture toughness, and crack propagation resistance, which surpass the capabilities of γ-TiAl alloy. It also boasts high specific strength and stiffness, along with excellent high-temperature creep resistance, making it a top choice for aerospace applications.

The conventional production of parts made with Ti2AINb is challenging owing to its poor room temperature ductility and thermal deformability. However, the rise of additive manufacturing (AM) has opened new avenues for manufacturing these complex parts.

The key to successful AM of Ti2AINb parts is high-quality powder production. BLT employs advanced inert gas atomization techniques and optimizes powder processing to significantly minimize satellite powder, enabling mass production of high-quality BLT-Ti2AlNb powder.

BLT-Ti2AlNb, with nominal composition of Ti-22Al-25Nb and size range of 15-53μm, boasts low density and excellent high-temperature oxidation resistance, making it suitable for continuous use at 800°C to 900°C. After heat treatment, parts made with BLT-Ti2AlNb demonstrate a tensile strength of 250-270MPa, yield strength of 140-160MPa, and elongation of 38.8%-42.8% at 900°C. BLT showcases its PBF-LB/M capability by producing a compact flow channel part for automatic liquid-cooled engines, featuring dozens of rectangular channels on the inner and outer walls of the part, with the thinnest wall being only 1mm thick.

Process parameters such as scan speed, laser power, scan spacing, and preheat temperature have significant impacts on the forming and properties of Ti2AlNb parts. By optimizing these parameters, BLT has identified a reliable process window suitable for producing dense, crack-free Ti2AlNb-based alloy parts. These parameters are now applicable across all its equipment models on the market.

Despite the significant attention received by Ti2AlNb globally, successful AM production remains rare, and related research is still in its infancy. With the mass production of high-quality BLT- Ti2AlNb powder, BLT is expected to drive further research in AM process, microstructure and properties of Ti2AlNb, which will advance its large-scale engineering applications.