This Small Business Innovation Research (SBIR) Phase I project addresses challenges in producing an industrially-feasible alternative to rare-earth-based magnets. Rare earths comprise over 65% of all magnets in use today, which are sourced almost exclusively from China, and their production poses serious environmental concerns. While small samples of exotic materials can be produced in labs, this project aims to demonstrate the feasibility of producing a viable material at industrial volumes. The project addresses this challenge from two fronts: by evaluating a manufacturing scheme that is new to this class of material (magnets), and by producing a new type of material. The process innovation is the establishment of supercritical conditions in a continuous flow technology using a technology called ?microreactors?. This enhancement enables the manufacturing of difficult-to-stabilize nanoparticles at industrial scales by eliminating problems related to alternative formulations and facilitates the refinement of the final product. The second innovation is the discovery of a new ferromagnetic material based upon nanoscale cobalt carbide particles. The combination of the process with the product results in a material with superior cost performance compared to that of rare earth magnets in a wide range of applications.
The broader impact/commercial potential of this project is the future mitigation of supply and pricing risk in the magnet supply chain due to an imminent shortage of rare earths. Further, this innovation is expected to prove disruptive to existing global markets, will help reinvigorate the US manufacturing industry by creating skilled jobs on US soil, and will help offset the environmental impact associated with the mining and refinement of rare earths. The magnet described herein will be a price-competitive alternative to all commercial magnet types, including rare earth magnets, in a number of applications. In the short term, it will help absorb unmet demand arising from the rare earth shortage. In the long term, it should penetrate a wide range of markets. The total global market for this product is on the order of several hundred million dollars. Finally, by reducing the reliance on rare earth materials, this magnet alleviates national security risks associated with shortages in Chinese sources for rare earths. The research will extend the use of an existing technology-microreactors-to make completely new materials, thus building a basis for new production technologies and making feasible new materials categories.
Nanofoundry, LLC has pioneered the combination of supercritical continuous flow nanomaterial processing with statistical modeling to optimize material yield, quality, and crystallinity while improving reactor design and efficiency. Our process is based around a patent-pending supercritical flow reactor which is superior to batch processing in several ways including heat transfer, solvent recovery, total output, and environmental impact. The purpose of this research was to further the development of a commercially-viable process to manufacture magnetic material that has the potential to displace rare earth magnets in many applications. Today approximately 70% of the global magnet supply is sourced from China, which represents a risk in the supply chain for this strategically- and economically-critical material. During this project, Nanofoundry generated a set of statistical models that characterized the effectiveness of process parameters—including: reactant concentrations and compositions, reaction temperature and pressure, and reaction time—on product shape and size and other characteristics. Nanofoundry’s team evaluated these variables utilizing Cobalt nanoparticles as the base case. Cobalt was chosen as it is a thoroughly studied transition metal with uses in a wide variety of electronic applications. This provided our team with a large body of knowledge to compare our process with, while working with a material of significant commercial value. Our primary goal was to generate Cobalt nanoparticles at a rate of greater than 1 gram/hour with the assistance and guidance of our statistical modeling software. Through the combination of enhanced model quality and reactor modifications we were able to generate greater than 4 grams/hour of Cobalt in continuous process. We were we able to create a material at a production rate of 400% of our original goal, and the material quality was superior to presently available Cobalt nanomaterials with an enhanced crystallinity compared to simple batch reactions. This work has set the stage for the continued advancement of continuous flow chemical reactors for the generation of metallic nanoparticles in commercial quantities thus allowing for the adaptation of other nanoparticle systems to our innovative flow technology. Ultimately this continuous flow technology will serve to increase the utilization of a wide variety of nanoparticles in various commercial sectors as production volume limitations are eliminated through continuous reactor scale up operations.
