Abstract

Joining of Ti2AlNb alloy to TiAl intermetallics was conducted by the newly-developed Ti–Ni–Nb–Zr brazing filler alloy. The microstructure evolution of the joints was investigated by scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and electron backscatter diffraction (EBSD). The macro-micro mechanical properties were studied by shear test and nano-indentation test. Typical interfacial microstructures across the brazing seam were Ti2AlNb substrate, α2-Ti3Al+β-Ti, γ-TiAl+Ti2Ni+TiNi+α2-Ti3Al, α2-Ti3Al+β-Ti, TiAl substrate. The Ti2Ni phase were firstly dissolved in the joints brazed at 1000 °C for 10 min and then precipitated after a prolonged holding time of 15 min. The nano-indentation test revealed that Ti2Ni phase exhibited the highest hardness of 12.60 GPa. The joints brazed at 1000 °C/15 min presented the maximum shear strength of 271 MPa. The dissolution and precipitation behavior of Ti2Ni phase was also discussed.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call