Friction Consolidation of Gas-Atomized Fe-Si Powders for Soft Magnetic Applications

Journal Article · 01 January 2017 · Materials Characterization

DOI:https://doi.org/10.1016/j.matchar.2016.11.026· OSTI ID:1339795

Jiang, Xiujuan; Whalen, Scott A.; Darsell, Jens T.; Mathaudhu, Suveen; Overman, Nicole R.

Soft magnetic materials are often limited in scalability due to conventional processes that do not retain beneficial microstructures, and their associated physical properties, during densification. In this work, friction consolidation (FC) has been studied to fabricate Fe-Si soft magnetic materials from gas-atomized powder precursors. Fe-Si powder is consolidated using variable pressure and tool rotation speed in an effort to evaluate this unique densification approach for potential improvements in magnetic properties. FC, due to the high shear deformation involved, is shown to result in uniform gradual grain structure refinement across the consolidated workpiece from the center nearest the tool to the edge. Magnetic properties along different orientations indicate little, if any, textural orientation in the refined grain structure. The effect of annealing on the magnetic properties is evaluated and shown to decrease coercivity. FC processing was able to retain the magnetization of the original gas-atomized powders but further process optimization is needed to reach the optimal coercivity for the soft magnetic materials applications.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1339795
• Report Number(s): PNNL-SA-120598
• Journal Information: Materials Characterization, Journal Name: Materials Characterization Vol. 123; ISSN 1044-5803
• Publisher: Elsevier
• Country of Publication: United States
• Language: English