Ti₂AlNb (Ti–22Al–25Nb at.%, nominal composition) intermetallic is essential to aerospace industry from a weight reduction perspective, and brings a possibility of replacing some Ni-based superalloys. Despite evaporation of element Al (from its original composition 22.8 at.% to 18.5 at.%), selective laser melting (SLM) technology offers distinct advantages in fabricating Ti₂AlNb intermetallic with superior room-temperature properties. A full understanding of corresponding heat treatment mechanism is the key to utilize well the SLM-prepared Ti₂AlNb at high temperatures. This study aims to clarify the relationship between the microstructure and mechanical propensities of SLM-prepared then heat-treated Ti₂AlNb, to ultimately achieve promising mechanical performances at high temperatures. For this research purpose, a series of heat treatments were conducted, and the corresponding microstructures, mechanical properties were systematic studied by advanced characterization techniques. Results show that the mechanical properties at both room and high temperatures depend on heat treatment adopted. The samples solution-treated at 950 °C and then aged at 700 °C show promising room and high temperature strengths due to the formation of acicular O, α₂ and grain boundary α₂ phases. However, their ductility was poor. Aging at 830 °C reduces the strength, but significantly improves the ductility due to the appearance of rodlike O phase and the increase of B2/β phase proportion. The alloy possesses promising strength and ductility (611 MPa, 10.0%) and high thermal stability at 650 °C. It is further demonstrated that the heat-treated Ti₂AlNb possesses promising specific strength, even higher than that of as-cast Inconel 718 superalloy. The developed alloy, therefore, has a high potential for the industries requiring high-temperature performance and weight reduction.

从减轻重量的角度来看，Ti ₂ AlNb（Ti-22Al-25Nb at。％，标称组成）金属间化合物对航空航天工业至关重要，并带来了替代某些镍基高温合金的可能性。尽管蒸发了元素Al（从其原始成分22.8 at。％到18.5 at。％），选择性激光熔化（SLM）技术在制造具有优异室温性能的Ti ₂ AlNb金属间化合物方面仍具有明显优势。充分了解相应的热处理机制是在高温下充分利用SLM制备的Ti ₂ AlNb的关键。这项研究旨在阐明SLM制备然后热处理的Ti ₂的微观结构与力学性能之间的关系。AlNb，以最终在高温下实现有希望的机械性能。为此目的，进行了一系列热处理，并通过先进的表征技术对相应的显微组织，力学性能进行了系统研究。结果表明，室温和高温下的机械性能均取决于所采用的热处理。将样品溶液处理，在950℃，然后熟化在700℃C显示有希望的室温和高温强度，由于针状的O的形成，α ₂和晶界α ₂阶段。但是，它们的延展性差。在830°C下时效会降低强度，但由于棒状O相的出现和B2 /β相比例的增加而显着提高了延展性。该合金具有令人满意的强度和延展性（611 MPa，10.0％），在650°C时具有很高的热稳定性。进一步证明，经热处理的Ti ₂ AlNb具有令人满意的比强度，甚至比铸态Inconel 718高温合金更高。因此，开发的合金在需要高温性能和减轻重量的行业中具有很高的潜力。