Printing rare-earth-free (REF) magnetic inks: synthesis, formulation, and device applications

Area of Science:

• Materials Science
• Nanotechnology
• Additive Manufacturing

Background:

• Additive manufacturing (AM) of magnetic materials faces limitations due to the cost and supply chain risks of rare-earth-element (REE) precursors.
• Recent nanomanufacturing advances enable rare-earth-free (REF) magnetic materials as viable alternatives for printable high-performance magnetic devices.

Purpose of the Study:

• To provide a comprehensive overview of recent developments in rare-earth-free (REF) magnetic materials for additive manufacturing.
• To discuss synthesis strategies, ink formulation, and integration into various AM processes.
• To highlight the structure-processing-property relationships for designing next-generation printable magnetic systems.

Main Methods:

• Review of synthesis strategies for REF magnetic materials and nanomaterials.
• Analysis of magnetic ink formulation, rheology, and properties.
• Examination of adaptability to AM techniques including direct ink writing, inkjet, aerosol jet, and screen printing.

Main Results:

• Exploration of diverse REF magnetic materials like spinel ferrites, hexaferrites, MnAl, MnBi, Alnico, FePt, and iron oxides/nitrides.
• Discussion of advancements in materials chemistry and ink rheology for printable magnetic systems.
• Emphasis on the impact of REF material structure on device functionality and performance.

Conclusions:

• Additive manufacturing of REF magnetic inks presents a scalable, cost-effective, and sustainable approach for future magnetic devices.
• Understanding the structure-processing-property relationship is crucial for optimizing REF magnetic ink design.
• Emerging opportunities and challenges exist in the field of printable REF magnetic materials.