The effect of heat treatment on the structure and properties of a heat-resistant nickel alloy based on Ni–Fe–Co–Nb–Ti–Ta

Abstract

The effect of heat treatment on the structure and properties of a new weldable heat-resistant alloy based on Ni–Fe–Co–Nb–Ti–Тa with a low coefficient of thermal expansion for parts of gas turbine engines was studied. The stability of the intermetallic globular phase, the features of precipitation of lamellar particles during annealing after quenching were studied. It is shown that the structure formed during heat treatment with nanosized cuboid and rounded particles of the γ′-phase, as well as with a small amount of lamellar η-phase precipitates along the grain boundaries, provides a high set of properties and excellence heat-resistance in comparison with iron-nickel commercial alloys of a similar purpose. With uniform precipitation of the γ′-phase higher tensile strength are achieved.