Soft magnetic composites produced by additive manufacturing

• Grant number: 21/12056-7
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: July 01, 2022
• End date: June 30, 2024
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Physical Metallurgy
• Principal Investigator: Piter Gargarella
• Grantee: Angelo Fernandes Andreoli
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Associated research grant: 16/11309-0 - The study, development and application of a hybrid process: Additive Manufacturing (AM) plus High Speed Machining/Grinding (HSM/G), AP.TEM

Abstract

The development of better performing electrical machines implies in the improvement of soft magnetic materials with lower losses due to hysteresis and eddy currents. Electric steels (Fe-Si) have long been used as ferromagnetic material in electrical machine cores. Despite being of low cost, Fe-Si steels with Si content up to 3.2% in weight have low electrical resistivity, which generates large losses due to eddy currents. With an increase in the Si content, the electrical resistivity and magnetic properties are improved, but on the other hand, the material becomes brittle, which in turn makes the manufacturing process more complex. To increase resistance to eddy currents, the core is formed by thin sheets of Fe-Si steel and with an insulating layer between successive laminations. This geometric configuration is reproducible by additive manufacturing, which creates almost totally dense metallic components, layer by layer, directly from computer-aided design data. This project aims to manufacture and study the metallurgical, mechanical, and magnetic characteristics of soft magnetic composites with alternating layers of Fe-Si steel (Fe-6.9Si) and a material with higher electrical resistivity (intermetallics, ceramic metals, or silica glass) by additive manufacturing. The composites are expected to have a low eddy current loss due to layers of soft magnetic material developed based on Fe-Si steel and layers of a material with higher resistivity such as an intermetallic material. The objective is to explore combinations producing composites with better magnetic performance in terms of eddy current losses and, therefore, lower energy consumption in electrical machines. The metallic powders, produced by gas atomization, will be characterized and used in the selective laser melting process. After producing distinct composites, these will be characterized by different techniques. The magnetic and mechanical properties will be evaluated as a function of chemical composition, microstructure, and additive manufacturing process parameters. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

MATHIAS, LAURA E. T.; ANDREOLI, ANGELO F.; GARGARELLA, PITER. Gas atomization of A2 tool steel: Effect of process parameters on powders' physical properties. Journal of Alloys and Compounds, v. 960, p. 9-pg., 2023-06-04. (17/27031-4, 21/12056-7)