Stornelli Giulia, Faba Antonio, Di Schino Andrea, Folgarait Paolo, Ridolfi Maria Rita, Cardelli Ermanno, Montanari Roberto
Dipartimento di Ingegneria Industriale, Università degli Studi di Roma "Tor Vergata", Via del Politecnico 1, 00133 Roma, Italy.
Dipartimento di Ingegneria, Università degli Studi di Perugia, Via G. Duranti, 06125 Perugia, Italy.
Materials (Basel). 2021 Mar 18;14(6):1489. doi: 10.3390/ma14061489.
In this paper, the best laser powder bed fusion (L-PBF) printing conditions for FeSi steels with two different Si content (3.0% and 6.5%) are defined. Results show very strict processing window parameters, following a lack of fusion porosity at low specific energy values and keyhole porosity in correspondence with high specific energy values. The obtained microstructure consists of grains with epitaxial growth starting from the grains already solidified in the underling layer. This allows the continuous growth of the columnar grains, directed parallel to the built direction of the component. The magnetic behaviour of FeSi6.5 samples, although the performances found do not still fully reach those of the best commercial electrical steels (used to manufacture magnetic cores of electrical machines and other similar magnetic components), appears to be quite promising. An improvement of the printing process to obtain thin sheets with increased Si content, less than 0.5 mm thick, with accurate geometry and robust structures, can result to an interesting technology for specific application where complex geometries and sophisticated shapes are required, avoiding mechanical machining processes for electrical steel with high silicon content.
本文确定了两种不同硅含量（3.0%和6.5%）的铁硅钢的最佳激光粉末床熔融（L-PBF）打印条件。结果显示出非常严格的工艺窗口参数，低比能量值时会出现未熔合孔隙，高比能量值时会出现匙孔孔隙。所获得的微观结构由从底层已凝固的晶粒开始外延生长的晶粒组成。这使得柱状晶粒能够沿与部件的构建方向平行的方向持续生长。FeSi6.5样品的磁性能虽然所发现的性能尚未完全达到最佳商用电工钢（用于制造电机磁芯和其他类似磁性部件）的性能，但似乎很有前景。改进打印工艺以获得厚度小于0.5毫米、具有精确几何形状和坚固结构的高硅含量薄片，对于需要复杂几何形状和精密形状的特定应用而言，可能会成为一项有趣的技术，避免了对高硅电工钢进行机械加工。
