Continuous Casting of TiAlNb Alloys with Different Velocities by Mixing Binary TiAl Ingot and Nb Wire

A method of continuous casting is used and the research investigates microstructure and mechanical properties under different drawing velocity (R, mm/min). The results show that microstructure and composition measurement of different zones are uniform. The smallest grain size is 25.93 μm and formability is good with 0.5R. Compressive strength is higher with 0.5R and maximum value is 1697MPa. Fracture toughness with 0.5R improves about 35.7% which is 21.7MPa·m1/2. The fracture morphology is trans-lamellar fracture and interface de-lamination. The method is a feasible way to continuously cast the TiAl-Nb alloys. The R is an important parameter to add high-melting-point element, which affects solidified temperature interval of solidification front and electromagnetic stirring.