Abstract:Characteristics of microstructure, inclusions, Prior Particle Boundary , Thermally Induced Porosity , defects and several large size disk′s tensile properties, stress rupture life ,low cycle fatigue of a P/M superalloy FGH97, which was made by Argon Atomization (AA) + Hot Isostatic Pressing (HIP)process, were investigated. The results reveal that the grain size of FGH97 material prepared by AA + HIP +Heat Treatment is ASTM 8-9. No continuous network PPB is found, and there is a very small amount of TIP. The size of mostly square γ' is about 200 nm, and grain boundary γ' is 1.5 to 2 μm. No coarse γ' phase and coarse carbides are observed. The average stress rupture time of 650 °C / 980MPa is 449 h. The maximum low cycle fatigue life is 258,909 cycles at 650 ℃, the average cycle reaches 19,014 cycles. The room temperature, 650℃, 750 ℃tensile properties, stress reputure performance at 650 ℃ / 980 MPa and the fracture life of Low cycle fatigue at 650 ℃ meet the FGH97 alloy technical requirements.