Brazing of alloys based on intermetallic phase Ni3Al

Alloys based on an intermetallic phase type Ni3Al-gamma' belong to a new generation of metallic materials intended for use at higher temperatures and are characterized by properties intermediate between those typical of metals and those characteristic of ceramics. The features of the alloys in question include a high melting point and high-temperature creep resistance, resistance to chemical and gaseous corrosion (oxidation), high resistance to abrasion, recrystallization and creeping as well as relatively low density. The alloys are difficult to weld, and therefore constitute a significant research and technological challenge. One of the methods applied in joining such materials as well as joining them with stainless steels and nickel alloys is brazing. This paper presents results of technological tests focused on the brazing of an alloy based on the phase Ni3Al-gamma' (also with stainless steel) with copper (Cu) and silver filler materials (Ag72Cu28). In addition, the results of mechanical and structural tests related to the previously mentioned joints are discussed.