Manufacturing of topology optimized soft magnetic core through 3D printing

Soft magnetic cores of electrical machines are typically made of electrical steel sheets by stacking them together. Recent development of powder bed processing of metal printing, e.g., through selective laser melting, is opening up interesting opportunities in the field of electromechanics, too [1], [2]. Selective laser melting is a process where objects are formulated by melting powder particles together layer by layer.Application of additive manufacturing in the production of soft magnetic cores, especially those of reluctance machines, appears interesting and potentially groundbreaking. Soft magnetic cores are used in electrical machines to guide the flux and to improve the performance. More comprehensive optimization of the magnetic circuit without the limitations of conventional subtractive and formative manufacturing methods can result in designs with significantly enhanced performance and notably lower material consumption and costs. The former is particularly true for the transverse flux reluctance machines [3].While the possible gains of 3D printing in electrical machine manufacturing have been lately addressed in some publications [2], the number of practical examples presented in the literature is rather limited. In this work, we study the manufacturing of the soft magnetic cores through selective laser melting and perform a characterization of the samples. Our main objectives are to explore: 1) how suitable typical materials of soft magnetic cores are for selective laser melting, 2) how well the characteristics of the printed samples meet the requirements of modern electrical machines.