Stray Magnetic Field Measurement Method of Magnetic Hysteresis Curve of Open-Ended Sensor and Actuator Cores.

Featured Application: The proposed measuring workstation, based on a stray magnetic field measurement method, can be generally used in applications where the magnetic hysteresis curves of long open-ended ferromagnetic components need to be determined to describe their magnetic behavior. The current design of the workstation allows measuring the magnetic characteristics of samples with a length and diameter of up to 100 mm and 10 mm, respectively. Therefore, it has already been used to reconstruct the magnetic hysteresis curves of ferromagnetic cores utilized in spacecraft and magnetometric devices and to determine the magnetic properties of various construction components of a complex sensor system to describe their response to an applied magnetic field. In the design and development of measurement systems, such as magnetometric security systems or sophisticated devices such as satellites, it is necessary to consider the magnetic properties of all its parts and components, especially if it contains any magnetometric subsystem. The magnetic parameters of the materials are generally well described by the manufacturers in relation to their unprocessed raw state. However, their magnetic properties change as the subsequent machining or heat treatment is performed. These behavioral reactions of the material may lead to changes in its hysteresis during the magnetization cycles. This effect is necessary to consider, especially in the case of metallic ribbons, the magnetic characteristics of which are usually estimated by measurements performed on toroidal cores. Since the magnetic properties of a toroidal core differ from the magnetic properties of the preferably used open-ended samples, the corresponding measurement method needs to be used to determine its magnetic characteristics. Therefore, in the proposed article, the authors present a stray magnetic field-based method and measuring workstation intended to measure the magnetic hysteresis curves of the ferromagnetic open-ended samples used in the applications concerning the magnetometric systems and stabilization subsystems of small satellites. The physical background of the measurement method is described in detail, as well as the hardware and software used. The magnetic hysteresis curves of a small satellite electromagnetic actuator were measured as an example of an open-ended ferromagnetic component produced from amorphous ribbons, the permeability of which differs in comparison to manufacturer-stated permeability of raw amorphous material. The results are supplemented by measurements of the core characteristics of the used magnetometer probe, as well as by the characteristics of the semi-produced materials used for the production of both investigated cores. The primary advantage of the presented measurement method lies in the ability of design validation prior to the production of the final component and its assembly. [ABSTRACT FROM AUTHOR]