Improving the Effectiveness of the Solid-Solution-Strengthening Elements Mo, Re, Ru and W in Single-Crystalline Nickel-Based Superalloys

Metals

Steffen Neumeier¹  Nicklas Volz¹  Tobias Gaag²  Nils Ritter²  Alexandra Peters²  Daniel Gruber²  Carolin Körner²  Christopher Zenk² 

[1] Institute I, Department of Materials Science & Engineering, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), 91058 Erlangen, Germany;Institute II (WTM), Department of Materials Science & Engineering, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), 91058 Erlangen, Germany;

关键词: Ni-based superalloys;    creep;    solid solution strengthening;    partitioning behavior;    DSC;    CALPHAD;   

DOI  :  10.3390/met11111707

来源: DOAJ

【 摘 要 】

Tailoring the partitioning behavior of solid solution strengtheners is a crucial design strategy for advanced Ni-based superalloys. The goal of this study was to maximize the enrichment of Mo, Re, Ru and W in the γ-matrix phase. To determine the composition dependency of the partitioning behavior, a set of polycrystalline superalloys with varying contents of these solid solution-strengthening elements and a W-containing single-crystalline alloy series with varying concentrations of the γ′-forming elements Ta and Ti was produced. Assessed properties include phase compositions by electron-probe micro-analysis, phase transformation temperatures by differential scanning calorimetry and creep behavior. Re exhibits the most pronounced enrichment in the γ-matrix, followed by Mo, Ru and W. Due to the preference of the Al-sites in the γ′-phase in the order Ta > Ti > W > Mo > Re, the solid solution strengthening elements Mo, Re and W are displaced from the γ′-phase by increasing Ti and Ta contents. The investigated solutes do not directly influence the partitioning behavior of Ru as it prefers Ni-sites in the γ′-phase. Compressive creep experiments reveal a correlation between the content of solid solution strengtheners in the γ-phase and creep performance.

【 授权许可】

Unknown