选区激光熔化制备钛铝合金研究进展

Owing to its high specific strength, creep resistance, oxidation resistance and low density, titanium aluminide (TiAl) alloy is regarded as an ideal candidate material to replace nickel-based superalloys for the fabrication of engine turbine blades used in aerospace applications. However, its application is restricted by poor plasticity at room temperature and difficulties in hot shaping. Compared with conventional subtractive manufacturing process, selective laser melting possesses some unique advantages such as short lead time, high processing resolution, near-net shape forming. Therefore, it can be used to remedy the deficiency of conventional subtractive manufacturing process and accelerate the application of TiAl. The research progress of titanium aluminide manufactured by selective laser melting were summarized. The effect of chemical composition, powder morphology, printing parameters and post-printing heat treatment on the printing defects, phase constitutes, microstructure and mechanical properties was reviewed. Finally, the future developing directions of SLM TiAl were prospected.