|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Gamma (FCC)/Gamma-Prime (L12) Co-Based Superalloys II
||The Influence of Cr in γ' Strengthened Co-base Superalloys
||Christopher H. Zenk, Ivan Povstugar, Steffen Neumeier, Mathias Göken
|On-Site Speaker (Planned)
||Christopher H. Zenk
It will be shown that the addition of Cr to Co-Al-W-alloys strongly affects the γ′ morphology and increases the γ′ volume fraction. APT shows that Cr partitions to the γ phase and Neutron diffraction reveals that this leads to a decrease of the γ/γ′ lattice misfit. The higher γ′ volume fraction, however, does not improve the mechanical properties. On the contrary, Cr additions reduce the creep strength. This can be partly explained by a change of the other elements’ partitioning behaviour. Additionally, a ternary low density γ′ strengthened Co-Ti-Cr alloy will be presented. The lattice misfit is sufficiently low to form a regular γ/γ′ microstructure. The γ′ volume fraction is above 60 % and the solvus temperature above 1100°C. The yield strength shows a distinct increase above 600°C and surpasses the one of a Co-Al-W-alloy.