CMMI-EPSRC: Multi-Driver Furnace Processing of Magneto-Functional Materials

Magnetic systems and materials are essential to modern society, permitting the interconversion of electrical, mechanical and, increasingly, thermal energies for the automotive, aerospace, energy and biomedical fields, among others. The need for more efficient and sustainable magnetic systems is acute, with both global end users and manufacturers acknowledging that magnetic materials with improved performance and comprised of non-critical elements are crucial for next-generation and future technologies. Improvements in performance can only be achieved through better understanding and control of the magnet structure at multiple scales during manufacture. To this end, this award applies an integrated experimental-computational approach to hone in on the roles of thermal, magnetic and/or strain fields in the development of magneto-functional materials during their construction from atoms to crystals and finally to useful microstructures. This project has the potential to realise new and sustainable materials and processes to support national prosperity, security and environmental imperatives. It develops a bilateral cohort of under-represented minority students who have interest in conducting research at the intersection of manufacturing, energy and environment.

Guided by first-principles nanoscale and finite element analysis (FEA) computation, testbed proxies including magnetostrictive and permanent magnet systems for technologically important magnetic materials will be processed using the Northeastern University custom-built lab-scale "MultiDriver" Furnace that can apply a saturating magnetic field and/or uniaxial stress during thermal treatment. In addition to uniform magnetic fields, the MultiDriver Furnace has the unique capability to apply a large yet entirely passive gradient magnetic field, offering the exciting prospect of accelerating elemental diffusion without the need for highly elevated temperatures that can damage microstructures. This proposal integrates a novel processing approach that is based on a fundamental Gibbs energy framework and relies on multi-scale computational insight for realising improved magnetic systems. The theoretical work is done in collaboration with researchers at the University of Warwick, UK. While the proposed techniques can be applied to almost any type of material, they have the greatest effects on magnetic materials as the magnetic response is extraordinarily sensitive to synthesis and processing effects (including degree/scale of crystallinity, chemical homogeneity, defect state and strain). The project generates new knowledge concerning unifying principles to identify the types and magnitudes of, and interactions between, various free energy terms that are important in magneto-responsive systems.