镍基高温合金Inconel 617时效过程中的相组成及γ′相演变规律研究

Study on the Phase Composition andγ′Phase Evolution of Nickel-based Superalloy Inconel 617 During Aging Process

研究了先进超超临界机组候选镍基高温合金Inconel 617的平衡相组成和时效过程中γ′相的演变规律,计算了不同温度下γ′相的平均直径、形状、数密度、形核速率和粒度分布。结果表明:Inconel 617的析出相包括γ相、γ′相、σ相、μ相及碳化物;γ′相的平衡析出量随着温度的降低而增大;随着时效时间的延长,γ′相的平均直径增大并发生立方化,形核速率减小,数密度先增大后减小;与时效时间相比,温度对γ′相粗化的影响更显著;γ′相粒度呈单峰分布,温度和时效时间对粒度分布的影响相似。

Through aging tests,the equilibrium phase composition and the evolution of γ′phase of nickel-based superalloy Inconel 617 for advanced ultra-supercritical units were studied.The average diameter,shape,numerical density,nucleation rate and particle size distribution of γ′phase were investigated at different temperatures.Results show that the precipitates of Inconel 617 include γ,γ′,σ,μ and carbides.The equilibrium precipitation amount of γ′phase increases with the reduction of aging temperature.As the aging process prolongs,the average diameter of γ′phase increases and undergoes cubization,the nucleation rate decreases,and the number density of γ′increases firstly and then decreases.Compared with the aging time,temperature has more significant effect on the coarsening of the γ′phase.The particle size of the γ′phase exhibits a unimodal distribution,and the effects of temperature and aging time on the particle size distribution are similar.