Abstract:Due to their low density, good room-temperature plasticity, and excellent high-temperature toughness, refractory niobium alloys have been used in hot-end components in the aerospace field. However, niobium alloys prepared by traditional casting methods are difficult to process parts with complex geometries, and face problems such as long production time, high cost and high buy-to-fly ratio. The rapid development of additive manufacturing technique in recent years not only shortens production time and lowers cost but also achieves superior mechanical properties, presenting new opportunities for the further application of niobium alloys. To this end, this paper reviews the current state-of-the-art research on additive manufactured niobium alloys focusing on the laser and electron-beam additive manufacturing of two generations of typical niobium alloys (namely C-103 and Nb521), with specific attention to the control of their mechanical properties and microstructure. In addition, common types of niobium alloys and additive manufacturing techniques are briefly introduced. Finally, the review outlines future research directions and identifies remaining challenges for this field. By reviewing the current state of additive manufactured niobium alloys, this paper provides a reference for the further application of niobium alloys in the aerospace field for hot-end components with complex structures.