Evolution of microstructure and mechanical properties of Ti modified superalloy Nimonic 80A

► Increase of the volume fraction of γ′ improved room temperature tensile strength. ► Precipitate of η phase at grain boundaries decreased the stress-rupture life. ► The orderly {1 1 1} planes at the γ′/γ interface was distorted by a/3 〈1 1 1〉 dislocation. ► The Cr23C6 had an orientation relationship with γ′/γ after stress-rupture tests. ► Decrease of the lattice misfit led to the morphology transformation of γ′ phase.