增材制造法制备的软磁材料Fe-6.5Si的断裂研究。

Investigation of Soft Magnetic Material Fe-6.5Si Fracture Obtained by Additive Manufacturing.

作者信息

Agapovichev Anton V, Khaimovich Alexander I, Erisov Yaroslav A, Ryazanov Mikhail V

机构信息

Engine Production Technology Department, Samara National Research University, 34 Moskovskoye Shosse, 443086 Samara, Russia.

Metal Forming Department, Samara National Research University, 34 Moskovskoye Shosse, 334086 Samara, Russia.

出版信息

Materials (Basel). 2022 Dec 13;15(24):8915. doi: 10.3390/ma15248915.

DOI:10.3390/ma15248915

PMID:36556719

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC9786061/

Abstract

The freeform capability additive manufacturing (AM) technique and the magnetic efficiency of Fe-6.5Si steel have the potential for the development of electromechanical component designs with thin body sections. Moreover, the directional anisotropy of the material, which is formed during growth, improves the magnetic and electrical properties of Fe-6.5 wt%Si. We obtained the range of optimal technological modes of Laser Power Bed Fusion process (volume energy density (VED) of 100−140 J/mm3, scanning speed of 750−500 mm/s) to produce the samples from Fe-6.5 wt%Si powder, but even at the best of them cracks may appear. The optical microscopy and SEM with EDX analysis of the laser-fabricated structures are applied for investigation of this phenomena. We detected a carbon content at the boundaries of the cracks. This suggests that one of the reasons for the crack formation is the presence of Fe3C in the area of the ordered α’FeSi (B2)+Fe3Si(D03) phases. Quantitative analysis based on crack initiation criteria (CIC) showed that the safe level of internal stresses in terms of the CIC criteria in the area of discontinuities is exceeded by almost 190%. Local precipitates of carbides in the area of cracks are explained by the heterogeneity and high dynamics of temperature fields, as well as the transfer of substances due to Marangoni convection, which, as a result, contributes to a significant segregation of elements and the formation of precipitate phases.

摘要

自由形状能力增材制造（AM）技术以及Fe-6.5Si钢的磁效率对于开发具有薄截面的机电部件设计具有潜力。此外，材料在生长过程中形成的定向各向异性改善了Fe-6.5 wt%Si的磁性能和电性能。我们获得了激光粉末床熔融工艺的最佳工艺模式范围（体积能量密度（VED）为100−140 J/mm3，扫描速度为750−500 mm/s），以便用Fe-6.5 wt%Si粉末制造样品，但即使在最佳工艺模式下仍可能出现裂纹。对激光制造结构进行光学显微镜和带有能谱分析（EDX）的扫描电子显微镜观察，以研究这种现象。我们在裂纹边界检测到了碳含量。这表明裂纹形成的原因之一是在有序的α’FeSi（B2）+Fe3Si（D03）相区域存在Fe3C。基于裂纹萌生准则（CIC）的定量分析表明，在不连续区域，就CIC准则而言，内应力的安全水平几乎超出了190%。裂纹区域碳化物的局部析出是由温度场的不均匀性和高动态性以及由于马兰戈尼对流导致的物质转移所解释的，结果导致元素的显著偏析和析出相的形成。