The effect of the solution and aging treatments on the microstructures and microhardness of nickel-based superalloy

Microstructure Evolution of a Nickel‐Based Powder Metallurgy Superalloy Under Different Solution Treatment Temperatures

“…Note that when the solution treatment temperature is elevated up by 10 °C above the γ′ solvus temperature, the particle size of secondary γ′ precipitates of the studied alloy increases only less than 10 nm, whereas as to the U720 Li (Ni–16Cr–14.7Co–3Mo–1.25 W–5Ti–2.5Al) superalloy it increases by 28.1 nm, [ 15 ] that of the Inconel 738 superalloy (Ni–16.7Cr–8.73Co–2.59Mo–4.98 W–2.76Ti–2.66Al) rose by 83 nm. [ 19 ] Thus, the alloying elements have a vital role in the coarsening of secondary γ′ precipitates.…”

“…83 nm. [19] These investigations suggested that the sizes of γ 0 precipitates in different alloys strongly depended on the solution treatment process. Furthermore, it was investigated that the MC carbides played an important role in hindering the migration of grain boundaries above the γ 0 solvus temperature.…”

“…In contrast, it has been revealed that the solution treatment temperature had a major impact on the morphologies of γ′ precipitates as well. [ 14,15,19 ] Hao et.al [ 20 ] found that the γ′ precipitates distribution in FGH100L superalloy became more uniform with the increasing solution temperatures. Moreover, the secondary γ′ precipitates gradually changed from spherical to cuboid shape, and became butterfly shape at 1150 °C.…”

“…Researchers also attempted to evaluate the impact of the solution temperature on the size evolution of secondary γ′ precipitates. [ 15,19 ] For instance, when the solution treatment temperature was elevated up by 10 °C near the γ′ solvus temperature, the particle size of γ′ precipitates of U720 Li superalloy increased by 28.1 nm, [ 15 ] whereas that of the Inconel 738 superalloy rose by 83 nm. [ 19 ] These investigations suggested that the sizes of γ′ precipitates in different alloys strongly depended on the solution treatment process.…”

“…[ 15,19 ] For instance, when the solution treatment temperature was elevated up by 10 °C near the γ′ solvus temperature, the particle size of γ′ precipitates of U720 Li superalloy increased by 28.1 nm, [ 15 ] whereas that of the Inconel 738 superalloy rose by 83 nm. [ 19 ] These investigations suggested that the sizes of γ′ precipitates in different alloys strongly depended on the solution treatment process. Furthermore, it was investigated that the MC carbides played an important role in hindering the migration of grain boundaries above the γ′ solvus temperature.…”