Study on microstructure and mechanical properties of GH909 after long time ageing

The microstructure and mechanical properties of superalloy GH909 after long time exposure up to 2000 h at 65O °C are studied. It is indicated that after long time exposure at 650 °C the quantity of Ε/Ε″ acicular phase increases and their sizes coarsen, the quantity of γ′ phase increases, the tensile strength of the alloy reduces and ductility increases, at 650 °C/510 MPa, notch rupture life increases. The microstructure and mechanical properties of the alloy after long time exposure up to 2000 h at 650 °C are still basically stable, the alloy GH909 has good combination properties.