Characterization and thermodynamic/kinetic analysis of nanoparticles in microstructures of single crystal superalloys
Gunther Eggeler, Ruhr-Universität Bochum, Bochum, GermanyVictoria Yardley, Ruhr-Universität Bochum, Bochum, GermanyAlireza Basir Parsa, Ruhr-Universität Bochum, Bochum , GermanyIvan Povstugar, MPIE, Düsseldorf, GermanyDierk Raabe, MPIE, Düsseldorf, Germany
Ni-base superalloys are known for their heat resistant γ / γ prime microstructures. Recently new tiny nano particles were discovered. Small (20 nm) spherical γ particles form in the large (0,5 µm) γ prime cubes, while small γ prime particles (10 to 30 nm) form in the wide (100 nm) γ channels. We use high resolution transmission electron microscopy (HR TEM) and 3D tomographic atom probe tomography (3D APT) to characterize the shape and the chemical composition of these nanoparticles. The thermodynamic and kinetic background of the formation of these nanoparticles is discussed in the light of previous results published in the literature.