Joining Between NiAl and Heat Resistant Alloys by Reactive Casting

NiAl is a low-density and high-strength structural material that has potential for use at temperatures higher than currently possible with conventional superalloys. However, NiAl is brittle at temperatures below 600 K, which is one of its most significant disadvantages and impedes its practical use as a structural material. A possible way to overcome this problem will be joining of it to ductile structural materials. The authors have recently developed a new technique named “reactive casting,” which enables the superheated liquid of a high-melting-point intermetallic compound to be produced without the need of external heating. In this study, they investigate the feasibility of joining between NiAl and heat resistant alloys such as nickel-base and iron-base alloys by the reactive casting method.