|About this Abstract
||2020 TMS Annual Meeting & Exhibition
||Microstructural Template Consisting of a Face-Centered Cubic Matrix with Ordered Precipitates: Microstructural Evolution and Properties
||A Nickel-based Superalloy Dual-reinforced by L12 Ni3Al and D022 Ni3V Ordered-fcc Precipitates
||Alexander J. Knowles, Lucy Reynolds, Vassili Vorontsov, David Dye
|On-Site Speaker (Planned)
||Alexander J. Knowles
Nickel based superalloys are widely used as high temperature materials owing to their combination of strength, creep, toughness, environmental resistance and microstructural stability in the 650–1200°C range. These exploit an fcc Ni matrix with L12 Ni3Al precipitates. However, there are other ordered-fcc structures where greater understanding is needed, for example, D022, as employed in Inconel 718, however, metastable Ni3Nb may decompose to D0a.
Here a nickel based superalloy has been produced reinforced by two different ordered-fcc intermetallic compounds, γ' L12 Ni3Al and γ’’ D022 Ni3V. Primary ageing at 900–1000°C precipitated spherical L12 Ni3Al, whose volume fraction and size were controlled by ageing temperature and time. Secondary ageing at 700°C precipitated laths of D022 Ni3V. The dual precipitation increased hardness by ~85 HV, with ∼500 MPa compressive strength at 800°C. Electron microscopy studied the Ni3Al precipitation and confirmed the form of the secondary Ni3V precipitates and their long-term stability.
||Planned: Supplemental Proceedings volume