Microstructure Characterization and Mechanical Properties of FGH 95 Turbine Blade Retainers

FGH 95 is a powder metallurgy (P/M) processed superalloy, which was developed in the 1980s in China. One of the applications of FGH 95 was high pressure turbine blade retainers. The manufacturing processes used to produce FGH 95 blade retainers consisted of atomization by plasma rotating electrode process (PREP), hot isostatic pressing (HIP) at super-solvus temperature and a sub-solvus solution heat treatment. The material had an equiaxed grain structure (ASTM 6, 5–7, 5). The γ' precipitates in as-HIP FGH 95 showed a tri-model distribution, Carbides in the alloy were MC type and precipitated at grain boundaries. The prior particle boundaries (PPB) in the material originated mainly from γ'z phase. Statistics of the mechanical properties data from batch production of the FGH 95 blade retainers were investigated. The as-HIP FGH 95 blade retainers showed high strength at room temperature and 650 °C, excellent creep resistance and outstanding stress rupture strength at 650 °C.