Production of Fe–Cr–Co-Based Magnets by Selective Laser Sintering
Dmitry Efremov, A. A. Gerasimova
Abstract
Abstract The study results of the potentials of selective laser melting (SLM), the so-called additive techniques, for production of permanent magnets have been considered. This process makes it possible to produce not only product models and prototypes but also finished functional products using layer-by-layer addition of material and binding of particles and layers to each other. An Fe–Cr–Co based alloy has been selected as a material to compare the technologies for permanent magnet production. The application fields of SLM have been considered; the powders obtained by different methods were taken for the studies. The classical technology of magnetic alloy casting has also been analyzed. The magnetic materials have been studied and the properties of powder magnets have been compared with reference data. Based on 25Kh15KA alloy powder sprayed by gas atomization, permanent magnets with a density of 7.59–7.55 g/cm3 can be manufactured using an SLM machine in accordance with GOST 24897–81. The magnet characteristics produced by SLM reach a level of magnets produced by classical metallurgical technologies. To study the magnetic and physical properties, four samples with the same geometry in the shape of a cube were produced. When producing each test sample, different operating modes of the SLM machine were selected. Samples were produced at the Central Research Institute of Structural Materials “Prometey” of National Research Center “Kurchatov Institute” as a part of the NIO-35 technological complex. It has been found that the characteristics of powders obtained by gas atomization are qualitatively better than the characteristics of powders obtained by other methods. The manufactured magnets meet all the requirements of GOST 24897–81.