The Magnetic Material Laboratory (MML Lab)
Central to our research group's distinction is the Magnetic Material Laboratory (MML Lab), a place of innovation in measurement techniques for soft and (soon) hard magnetic materials. Within this laboratory, we possess an array of measurement devices, including:
- Rotational Single Sheet Tester (RSST): This device is instrumental in the measurement of magnetic parameters for thin steel sheets, encompassing both electric steel sheets found in electric machines and anisotropic sheets used in power transformers. We evaluate uniaxial and rotational losses, enhancing our ability to bridge the gap between theoretical understanding and real-world material characterization.
- Epsteinframe: Our Epsteinframe enables us to conduct classical measurements for pure uniaxial magnetic property characterization. With the addition of a Thermojet, we can extend our measurements from -20°C to 180°C.
- Helmholtz Coils: An array of Helmholtz coils assists in characterizing solid rod materials and calibrating magnetic sensors, such as H-coils, B-coils, and Hall sensors.
Magnetic Coordinate Measurement Machine (MCMM): The MCMM serves as a crucial device in our lab, enabling the 3D scanning of hard magnets and the evaluation of magnetic field homogeneity. It also facilitates critical research on the impact of different cutting methods on electric steel sheets, strengthening the bond between theoretical understanding and practical industrial applications.
Our Magnetic Material Laboratory is a linchpin in our mission to bridge the gap between fundamental research and practical industrial application. Here, we meticulously evaluate magnetic materials, employing state-of-the-art devices to enhance scientific understanding and material characterization for real-world implementation.
Selected Projects
In-line determination of thermo-physical and electromagnetic properties from system data of induction heating facilities
COMET project with Materials Center Leoben Forschung GmbH (MCL)
The objective of the project is to develop methods to extract thermo-physical and electromagnetic material properties during induction heating processes from in-line machine data of facilities using induction heating (e.g., for preheating of forgings, heating of steel strips in continuous annealing/galvanizing lines and induction hardening involving austenitization and/or tempering), and from an independent sensor/software system that can be easily integrated in production systems related to induction heating but also in other industrial processes.
Induction heating test-rig at MCL Leoben
Design of electro sheet processing for improved efficiency of e-mobile drives
COMET project with Materials Center Leoben Forschung GmbH (MCL)
The objective of the project is the design of electrical steel sheets for improved efficiency of e-mobile drives, exhibiting improved magnetic properties due to customtailored processing of the sheet material leading to an optimized microstructure, and reducing the detrimental effect of punching on the electromagnetic losses near the sheet edges.
Determination of local magnetic properties via a sensor-actuator system including an inverse scheme
Part of SFB (TRR 361) Project D04
To modulate the magnetic field intensity with precision, we are working on an electromagnet comprising an iron core and an excitation coil, as visually represented in the figure below. Our design concept encompasses the complete integration of Hall and Giant Magnetic Resistance (GMR) sensor arrays with the electromagnet. This approach allows us to capture magnetic induction data through an array of Hall sensors, which measure the magnetic field's thickness direction, and GMR sensors. With this data it is possible to identify the locally varying magnetic material properties via an inverse scheme, which is or great importance, e.g., when dealing with the cutting process of electric steel sheets and the degradation of magnetic properties towards the cutting edges.
Physically based and numerically efficient hysteresis operators and finite element formulations
Part of SFB (TRR 361) Project D04
Within the framework of this project, our focus is directed towards the intricate domain of energy-based vector hysteresis models and the development of strategies for their seamless integration into computationally efficient finite element formulations. The paramount challenge we encounter pertains to the derivation of a thermodynamically consistent model for the energy-based hysteresis operator, one that adeptly accounts for rotational losses even in the presence of high field amplitudes. Subsequently, we shall proceed with the implementation of this model, followed by rigorous numerical simulations. We will also work on a meticulous comparison of simulation results with empirical data acquired through our rotational single sheet tester.
Model Order Reduction Techniques applied to Electromagnetic Compatibility Simulations
Workpackage 4 at CEMC Lab (SAL)
The SAL GEMC Lab focuses on electromagnetic compatibility (EMC) investigations of electronic based systems. Herein, the main goal of work-package 4 is the application of model order reduction (MOR) techniques to approximate the input-output behaviour of a half bridge PCB which is a demonstrator of the SAL GEMC Lab. Therefore, the PCB is investigated with the quasi-stationary Darwin formulaion using finite element (FE) method to take the resistive, inductive and capacitive effects into account. Further, the spatial discretisation of the FE formulation leads to a differential- algebraic equation which allows the application of different MOR methods.
