Novel Microstructures and Enhanced Properties Through High Magnetic Field Treatment and Extraordinary Thermomechanical Processing in Ferromagnetic Alloys

University Of Virginia Main Campus, Charlottesville VA

Investigators

Abstract

TECHNICAL: The major thrust of this research program is to systematically explore the application of high magnetic field processing coupled with far-from-equilibrium (FFE) materials synthesis and a "combined reactions" approach as a tool for tailoring the length scales and morphologies of transformation products in select ferromagnetic alloys. The goal is to use this hybrid processing and heat treatment to drive the transformation behavior and microstructural evolution along reaction paths generally not accessible to conventional processing methodologies and produce unique structural states with enhanced physical, mechanical and chemical properties. The combined reactions approach involves inducing two or more solid state transformations, e.g. recrystallization and ordering/decomposition, to occur concomitantly, sequentially and/or synergistically. The Fe-Pd and Mn-Al-(C) permanent magnet alloys are chosen for the studies based on their rich transformation behavior and highly structure-sensitive magnetic properties. The materials processing strategy is expected to produce ultra-fine microstructures including bulk nanostructured ferromagnets as indicated by preliminary results. The high magnetic field processing will be carried out in cooperation with the Oak Ridge National Laboratory (ORNL) Materials Processing Group and the National High Magnetic Field Laboratory (NHMFL) at Florida State University. NON-TECHNICAL: This research should contribute directly to the development of the so-called electromagnetic processing of materials (EPM), particularly the science relating to high magnetic field processing as a potentially viable new industrial approach to tailoring unique materials including nanostructured steels and bulk ferromagnets. This new dimension in advanced materials processing could catalyze the advent of a new era in currently mature and well-entrenched technologies such as the steel industry as well as impacting rapidly emerging areas such as nanotechnology. Importantly, although the research addresses two particular ferromagnetic alloy systems, the project is aimed at establishing a fundamental basis for understanding the complex interplay of thermodynamic, kinetic and mechanistic factors involved which will be generally applicable to a range of materials. In addition to an ambitious research agenda, a substantial education and outreach component has been developed involving three main parts: 1) Hands-on-Science (HOS) laboratory experience for secondary school students. 2) Workshops for Secondary School Science Teachers (Magnetism and Modern Technology). 3) Interaction with ORNL and the placement of URA students as liaison researchers between ORNL and the University of Virginia (UVA). The URA positions will be used effectively to attract minorities and women to careers in engineering and science.