Cracking of soft magnetic FeSi to reduce eddy current losses in stator cores
Cracking of soft magnetic FeSi to reduce eddy current losses in stator cores
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DOI：
10.1016/j.addma.2023.103555
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发表时间：
2023-04
影响因子：
11
通讯作者：
Alexander D. Goodall;L. Chechik;R. Mitchell;G. Jewell;I. Todd
中科院分区：
文献类型：
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作者：
Alexander D. Goodall;L. Chechik;R. Mitchell;G. Jewell;I. Todd
为了能够在电机中使用增材制造（AM）软磁材料，必须避免大体积横截面，因为它们允许大的涡流，从而降低效率。Fe-6.5wt%Si是一种优良的软磁材料，但脆性大。在这项研究中，我们利用这种材料的固有特性，在AM材料内开发裂纹网络，以抑制寄生涡流。通过操纵激光参数和扫描策略有目的地诱导开裂，材料的有效电阻率可以增加到206 µΩ·cm，是材料82 µΩ·cm高电阻率的250%。裂纹密度随扫描速度的降低而增加，计算出的电弯曲度与有效电阻率相关。示出不同的扫描策略来改变裂纹的取向，表明裂纹取向可以相对于磁通量来控制，在涡流的平面中提供高电阻，同时保持磁性。该方法在1 T、50 Hz下产生2.2W/kg的损耗，类似于使用气隙的方法，但具有> 97%的高得多的堆叠因子，优于在软磁材料的AM中使用的其他方法，显示出制造复杂电机的定子的前景。
To enable use of additively manufactured (AM) soft magnetic material in electric machines, large bulk cross-sections must be avoided as they allow large eddy currents, reducing efficiency. Fe-6.5 wt%Si is an excellent soft magnetic material, but is brittle. In this study we exploit this inherent characteristic of the material to develop crack networks within the AM material to inhibit parasitic eddy currents. By manipulating the laser parameters and scan strategy to purposefully induce cracking, the effective resistivity of the material can be increased to 206 µΩ·cm, 250% of the materials’ already high resistivity of 82 µΩ·cm. Crack density is shown to increase with decreasing scan speed, and calculated electrical tortuosity shown to correlate with effective resistivity. Different scan strategies are shown to alter the orientation of the cracks, demonstrating that the crack orientation could be controlled in relation to the magnetic flux, providing high electrical resistance in the plane of the eddy currents, whilst maintaining magnetic properties. This method yields losses of 2.2 W/kg at 1 T, 50 Hz, similar to methods using air gaps, but with a much higher stacking factor of > 97%, outperforming other methods used in AM of soft magnetic material, showing promise for manufacturing stators of complex electric machines.