Effect of aging treatment on microstructure and properties of HEX+HIF FGH95 superalloys

Abstract

The FGH95 superalloy was processed through HIP + HEX + HIF, then the alloy was conducted by two different aging treatments, and the microstructure, morphology of precipitate phase and mechanical properties were studied. The results show that there is no obvious effect of aging treatments on the grain size, but the amount, the size distribution are obviously different. Compared to single-step aging treatment, double-step aging treatment can more effectively promote the growth of inner-grain γ' phase, the average diameter of inner-grain γ' phase can reach 78 nm, while that is 67 nm for single-step aging treatment. Meanwhile, double-step aging is more beneficial to the precipitation of inner-grain strenthening phases, such as M3B2 and etc. The tensile strength of the alloy with different aging is similar, but the endurance life of alloy with double-step aging is lower, and the endurance plasticity is higher.

Keywords

• extrusion
• isothermal forging
• fgh95 p/m superalloy
• aging treatment
• microstructure and property