Nickel-based superalloys exhibit exceptional mechanical properties at high temperatures and are key materials for turbine blades in jet engines and gas turbines. Since the mechanical properties of these superalloys depend strongly on the microstructure, the interaction of dislocations in the γ channels with the γ´ precipitates plays a significant role in the superior strength of these alloys at high temperatures.
Within the multiscale modeling framework of the collaborative research center SFB/Transregio 103 “From Atoms to Turbine Blades“ , we use atomistic simulations to study the processes during dislocation mediated high-temperature deformation of superalloys with γ/γ´-microstructure. For this purpose, we calculate the structure and properties of the relevant defects like dislocations, stacking faults, and the γ/γ´-interface and simulate the interaction between these defects.
Related movies: The movie below shows the generation of an atomistic simulation sample based on atom probe tomography data and the results of molecular dynamics simulations of a tensile test with one and two added channel dislocations.
Related publications:
A. Kirchmayer, H. Lyu, M. Pröbstle, F Houllé, A. Förner, D. Huenert, M. Göken, P.J. Felfer, E. Bitzek, S. Neumeier [2020], "Combining Experiments and Atom Probe Tomography‐Informed Simulations on γ′ Precipitation Strengthening in the Polycrystalline Ni‐Base Superalloy A718Plus", Advanced Engineering Materials 2000149 Link to paper
J.J. Möller, M. Mrovec, I. Bleskov, J. Neugebauer, T. Hammerschmidt, R. Drautz, C. Elsässer, T. Hickel, E. Bitzek [2018], "{110} planar faults in strained bcc metals: Origins and implications of a commonly observed artifact of classical potentials", Physical Review Materials 2 093606 Link to paper
F. Houllé, F. Walsh, A. Prakash, E. Bitzek [2018], "Atomistic Simulations of Compression Tests on γ-Precipitate Containing Ni3Al Nanocubes", Metallurgical and Materials Transactions A 49 4158–4166 Link to paper
A. Prakash, E. Bitzek [2017], "Idealized vs. Realistic Microstructures: An Atomistic Simulation Case Study on γ/γ′ Microstructures", Materials 10 88 Link to paper
A. Prakash, M. Hummel, S. Schmauder, E. Bitzek [2016], "Nanosculpt: A methodology for generating complex realistic configurations for atomistic simulations", MethodsX 3 219-230 Link to paper