BLT-Ti65, the next generation of high-temperature titanium alloy for advanced applications

24 7月
2024
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Ti65 is a multi-component, near α high-temperature titanium alloy known for its superior properties, including excellent strength, plasticity, creep resistance, corrosion resistance, and thermal stability at high temperatures up to 650°C. This performance places Ti65 well above the temperature limit of traditional titanium alloys, making it highly desirable in advanced applications such as aerospace, chemical equipment, and marine engineering.

However, additive manufacturing of Ti65 powder often leads to defects such as pores and cracks in unfused, unmelted/ partially melted powder particles and inter-orbit/ inter-layer delamination. These defects act as stress concentration areas, increasing the risk of material failure (fracture) and adversely affecting the performance of formed parts. In response, BLT’s powder R&D engineers have developed BLT-Ti65 suitable for Laser-based Powder Bed Fusion of Metals (PBF-LB/M) and directed energy deposition (DED).

BLT-Ti65 features a nominal chemical composition of Ti-5.9Al-4Sn-3.5Zr-0.3Mo-0.4Si-0.3Nb-2.0Ta-1.0W-0.05C, and is available in two size ranges: 15-53μm for PBF-LB/M and 75-180μm for DED. After heat treatment, components produced using 15-53μm BLT-Ti65 powder exhibit a yield strength of 483-503MPa, tensile strength of 604-624MPa, and elongation of 16.5%-26.5% at 650°C. Components made with 75-180μm BLT-Ti65 powder show a yield strength of 478-538MPa, tensile strength of 588-648MPa, and elongation of 22%-32% at 650°C.

By overcoming challenges such as the cracking and deformation control and printing process control of BLT-Ti65, BLT has developed forming process plans and forming parameters for BLT-Ti65, now applicable across all its equipment models on the market.

Through optimization of the composition, forming parameters and forming process control of Ti65, BLT has successfully developed BLT-Ti65 and verified its forming capability, which will provide more possibilities for the application of high-temperature titanium alloys in high-temperature-resistant components of aero-engines, scientific experiments involving new materials and structures and other fields.