Permanent magnet hysteresisgraph

Tampere University Foundation sr (Contracting authority) is publishing direct award notice for 'Permanent magnet hysteresisgraph', worth 57 530 € (excl. VAT). Within the last 4 (four) years similar instrument purchases from the same supplier total 121 555 € (excl. VAT). Other award notice(s): TAU/2512/2025 (25th of April, 2025)

BACKGROUND INFO The Electromechanics research group, led by Prof. Paavo Rasilo at Tampere University, works at the interface of electromagnetic theory, computational science, physics of magnetic materials, and electrical engineering applications of practical importance, focusing on electromagnetic and electromechanical conversion as well as superconducting magnets. Researchers develop numerical calculation techniques and magnetic material models to design and analyze devices such as rotating electrical machines, transformers, inductors, energy harvesters, and wireless power transfer systems. For all these purposes, it is essential to characterize a wide range of magnetic materials, from soft magnetic composites and electrical steels to permanent magnets. NEED The research group currently owns a hysteresisgraph for measuring soft magnetic materials, specifically the Remagraph C from Magnet-Physik, which allows various rod samples to be measured, as well as stacks of electrical sheets. However, these characteristics are always only quasi-stationary. In recent years, a Remacomp C from the same company has been acquired, which allows the measurement of hysteresis curves and power losses at frequencies up to 10 kHz, including non-harmonic waveforms. However, we are increasingly encountering the need to characterize permanent magnets, where it is necessary to know not only the major and minor hysteresis curves but also the recoil curves. Although AlNiCo magnets do not require as large a field for demagnetization as other permanent magnets, they cannot be measured with existing equipment, partly because of their shape, and a dedicated hysteresisgraph is required. The requirements for a hysteresisgraph are therefore: • Ability to measure major and minor hysteresis curves and recoil curves of AlNiCo magnets • Ability to fully magnetize and demagnetize AlNiCo magnets • Ability to precisely measure different magnet sizes and shapes (cylindrical / block) • Hardware and software compatibility with existing equipment CONCLUSION FOR DIRECT AWARD Permagraph L, Electromagnet EP3, and several sizes of measuring coils from Magnet-Physik fully meet our requirements for measuring AlNiCo magnets and fit within our budget limitations. Although hysteresisgraphs based on a similar principle are available from other companies (e.g., Brockhaus), they do not meet the requirement for compatibility with existing equipment. The selected device from Magnet-Physik will allow us to use the same fluxmeters, cables, computers, and file types for which follow-up processes already exist, and to have all measuring devices serviced and calibrated at the same time by the same company. The Permagraph L fluxmeter is an upgrade over the existing fluxmeters we have at our disposal and can also be used for other measurements, such as the Epstein frame or single-sheet tester. In the future, it will also allow for expansion with heated poles with feedback control for measuring magnets at elevated temperatures.