This project is a joint project of the De Magnete group and the Atom Probe Tomography group, and was initiated by MPIE’s participation in the CRC TR 270 HOMMAGE. We also benefit from additional collaborations with the “Machine-learning based data extraction from APT” project and the Defect Chemistry and Spectroscopy group.
Magnetic materials are key components of energy conversion devices and thus improving the material’s magnetic properties is critical to enhance the sustainability of power generation and conversion. We use atom probe tomography (APT) to study the relationship between the microstructure on the nanoscale and the properties of various soft and hard magnetic materials. As demonstrated by experiments and machine-learning aided analysis, the changes in magnetic properties, e.g., magnetization, coercivity, Curie temperature and domain structure, are closely related to the variation of magnets’ microstructure. Our results help guide the design of magnetic materials.
Several magnetic systems are currently under active investigation: NdFeB, Sm(Co,Fe), CeCoCu magnets as hard magnetic alloys and CoFeNiTaAl high-entropy alloys as soft magnets.
Fig: APT 3D map of the Sm2(Co,Fe,Cu,Zr)17 show different spatial arrangement of the three phases depending on the region: magnetic Cu-rich (blue) and Zr-rich (green) cell boundary phases inside Fe-rich matrix cell phase (grey).
Fig: APT 3D map of the Sm2(Co,Fe,Cu,Zr)17 show different spatial arrangement of the three phases depending on the region: magnetic Cu-rich (blue) and Zr-rich (green) cell boundary phases inside Fe-rich matrix cell phase (grey).
Many important phenomena occurring in polycrystalline materials under large plastic strain, like microstructure, deformation localization and in-grain texture evolution can be predicted by high-resolution modeling of crystals. Unfortunately, the simulation mesh gets distorted during the deformation because of the heterogeneity of the plastic…
In this project, links are being established between local chemical variation and the mechanical response of laser-processed metallic alloys and advanced materials.
Conventional alloy development methodologies which specify a single base element and several alloying elements have been unable to introduce new alloys at an acceptable rate for the increasingly specialised application requirements of modern technologies. An alternative alloy development strategy searches the previously unexplored central regions…
This project aims to correlate the localised electrical properties of ceramic materials and the defects present within their microstructure. A systematic approach has been developed to create crack-free deformation in oxides through nanoindentation, while the localised defects are probed in-situ SEM to study the electronic properties. A coupling…
A wide range of steels is nowadays used in Additive Manufacturing (AM). The different matrix microstructure components and phases such as austenite, ferrite, and martensite as well as the various precipitation phases such as intermetallic precipitates and carbides generally equip steels with a huge variability in microstructure and properties.
In collaboration with Dr. Edgar Rauch, SIMAP laboratory, Grenoble, and Dr. Wolfgang Ludwig, MATEIS, INSA Lyon, we are developing a correlative scanning precession electron diffraction and atom probe tomography method to access the three-dimensional (3D) crystallographic character and compositional information of nanomaterials with unprecedented…
With the support of DFG, in this project the interaction of H with mechanical, chemical and electrochemical properties in ferritic Fe-based alloys is investigated by the means of in-situ nanoindentation, which can characterize the mechanical behavior of independent features within a material upon the simultaneous charge of H.
This project is part of Correlative atomic structural and compositional investigations on Co and CoNi-based superalloys as a part of SFB/Transregio 103 project “Superalloy Single Crystals”. This project deals with the identifying the local atomic diffusional mechanisms occurring during creep of new Co and Co/Ni based superalloys by correlative…
In this project, we investigate a high angle grain boundary in elemental copper on the atomic scale which shows an alternating pattern of two different grain boundary phases. This work provides unprecedented views into the intrinsic mechanisms of GB phase transitions in simple elemental metals and opens entirely novel possibilities to kinetically engineer interfacial properties.
