The application of macroscopic flakes for Fe-6.5%Si bulk magnetics with superior magnetic properties
Silicon steel is the most popular crystalline soft magnetic material for motor and transformer applications. The material must be in thin thickness to reduce the eddy current loss. Conventional thin steel sheet manufacturing process starts with cast slab, followed by a series of hot/cold roll process. For transformer, thin sheet is wrapped to form the core; for motor, the sheet is stamped, coated, heat treated, and stacked to form stator/rotor. This process requires the steel to possess sufficient ductility. For Si steel, increasing Si content will improve its electrical and magnetic properties, but it will also lead to embrittlement with 3.5% Si as the limit for the conventional manufacturing processes. Despite poor mechanical properties, high Si steel, especially the one with 6.5% Si, is gaining more attention due to its lower iron loss, higher permeability, and near zero magnetostriction. To address the brittleness problem of the 6.5% Si steel, we developed a novel process, using rapid solidification to prepare thin flakes with high ductility, then using hot press to consolidate the flakes into near net shape bulk sample. The obtained Fe-6.5%Si sample with 0.2 mm thickness exhibits an iron loss of 7.2 W/kg at 400Hz and magnetic flux density of 1 Tesla, and a maximum permeability of 28,400. In addition, various coating materials and processes were investigated as inter-flake insulators for their effect on reducing the eddy current losses for thicker configuration.
- Research Organization:
- Iowa State Univ., Ames, IA (United States)
- Sponsoring Organization:
- USDOE Office of Energy Efficiency and Renewable Energy (EERE), Transportation Office. Vehicle Technologies Office
- DOE Contract Number:
- ee0007794
- OSTI ID:
- 1864106
- Resource Relation:
- Conference: 2019 Joint MMM-Intermag Conference
- Country of Publication:
- United States
- Language:
- English
Similar Records
The application of macroscopic flakes for Fe-6.5%Si bulk magnetics with superior magnetic properties
Enabling 6.5% Silicon Electric Steel for Motor Application