Rare Earth Crisis Research Articles

The Future of Permanent-Magnet-Based Electric Motors: How Will Rare Earths Affect Electrification?

In this review article, we focus on the relationship between permanent magnets and the electric motor, as this relationship has not been covered in a review paper before. With the increasing focus on battery research, other parts of the electric system have been neglected. To make electrification a smooth transition, as has been promised by governing bodies, we need to understand and improve the electric motor and its main component, the magnet. Today's review papers cover only the engineering perspective of the electric motor or the material-science perspective of the magnetic material, but not both together, which is a crucial part of understanding the needs of electric-motor design and the possibilities that a magnet can give them. We review the road that leads to today's state-of-the-art in electric motors and magnet design and give possible future roads to tackle the obstacles ahead and reach the goals of a fully electric transportation system. With new technologies now available, like additive manufacturing and artificial intelligence, electric motor designers have not yet exploited the possibilities the new freedom of design brings. New out-of-the-box designs will have to emerge to realize the full potential of the new technology. We also focus on the rare-earth crisis and how future price fluctuations can be avoided. Recycling plays a huge role in this, and developing a self-sustained circular economy will be critical, but the road to it is still very steep, as ongoing projects show.

Development of High-Performance Hot-Deformed Neodymium-Iron-Boron Magnets without Heavy Rare-Earth Elements.

Neodymium-iron-boron magnet is an essential material for the traction motors of green vehicles because it exhibits the highest maximum energy product, (BH)max, out of all permanent-magnet materials. However, heavy rare-earth elements such as dysprosium and terbium, which are scarce resources, are added to these magnets to improve their heat resistance. To address this resource problem, considerable efforts have been made to reduce the composition of heavy rare-earth elements in these magnets without causing a significant reduction in coercivity. Hot-deformed Nd-Fe-B magnets are a category of Nd-Fe-B magnets where precious materials such as heavy rare-earth elements can be eliminated or reduced to maintain high coercivity owing to their fine microstructure. Although they are not often used for the fabrication of high-performance magnets due to their complicated production process and the difficulty in controlling their fine microstructure, after the rare-earth crisis in 2020, these magnets have begun to attract attention as a material that could increase coercivity when controlling their microstructures. This paper provides an overview of hot-deformed magnets and the efforts made to improve their properties by controlling their microstructures.

Greener processing of SrFe12O19 ceramic permanent magnets by two-step sintering

With an annual production amounting to 800 kilotons, ferrite magnets constitute the largest family of permanent magnets in volume, a demand that will only increase as a consequence of the rare-earth crisis. With the global goal of building a climate-resilient future, strategies towards a greener manufacturing of ferrite magnets are of great interest. A new ceramic processing route for obtaining dense Sr-ferrite sintered magnets is presented here. Instead of the usual sintering process employed nowadays in ferrite magnet manufacturing that demands long dwell times, a shorter two-step sintering is designed to densify the ferrite ceramics. As a result of these processes, dense SrFe12O19 ceramic magnets with properties comparable to state-of-the-art ferrite magnets are obtained. In particular, the SrFe12O19 magnet containing 0.2% PVA and 0.6% wt SiO2 reaches a coercivity of 164 kA/m along with a 93% relative density. A reduction of 31% in energy consumption is achieved in the thermal treatment with respect to conventional sintering, which could lead to energy savings for the industry of the order of 7.109 kWh per year.

Magnetic performance of SrFe12O19–Zn0.2Fe2.8O4 hybrid magnets prepared by spark plasma sintering

In the last few years, significant effort has again been devoted to ferrite-based permanent magnet research due to the so-called rare-earth crisis. In particular, a quest to enhance ferrites maximum energy product, BH max, is underway. Here, the influence of composition and sintering conditions on the microstructure and consequently magnetic properties of strontium ferrite-based hybrid composites was investigated. The powder mixtures consisted of hydrothermally synthesised Sr-ferrite with hexagonally shaped platelets with a diameter of 1 μm and thickness up to 90 nm, and a soft magnetic phase in various ratios. Powders were sintered using a spark plasma sintering furnace. The crystal structure, composition and microstructure of the starting powders and hybrid magnets were examined. Their magnetic properties were evaluated by vibrating sample magnetometer, permeameter and by single-point-detection measurements.

Rare Earths in the Trade Dispute Between the US and China: A Déjà Vu

The trade dispute between the US and China has reached a point where export restrictions on rare earths have become a possible means for sanction. This contribution provides a succinct analysis of the current dependency of the US on rare earths from China and draws parallels to the events during the rare earth crisis of 2010 and 2011, which was caused by geopolitical tensions between Japan and China. Respective risks associated with restrictions on the trade of rare earths are considered. Findings suggest that Europe could be affected as well and should be better prepared to mitigate supply disruptions in rare earth trade. Potential mitigation strategies and consequences of the current developments for Europe are also discussed.

Quand une crise en cache une autre : la « crise des terres rares » entre géopolitique, finance et dégâts environnementaux

The expression “rare earth crisis” was used by a collection of actors in the United States, Europe and Japan to describe the situation created by the 2010-2011 surge in the global market prices of 17 metals occupying a strategic place in many industrial sectors and the fear that supplies would be disrupted following China’s adoption of export quotas. Yet this crisis – described both as a trade crisis and a geopolitical one – concealed a financial operation and major damage to the environment. This article adopts several perspectives to study what may be described as “interwoven crises”, paying special heed to J. Roitman and M. Dobry’s call to be attentive to the processes by which crises are labelled in addition to their dynamics and effects. Analysis is further enhanced by extending the timeframe of the analyzed circumstances, thus providing a better grasp of their longer-term dynamics and re-situating these critical situations in their temporal and spatial contexts.

Perspective and Prospects for Rare Earth Permanent Magnets

Abstract Rare earth permanent magnets constitute a mature technology, but the shock of the 2011 rare earth crisis led to the re-evaluation of many ideas from the 1980s and 1990s about possible new hard magnets containing little or no rare earth (or heavy rare earth). Nd–Fe–B magnets have been painstakingly and skillfully optimized for a wide range of applications in which high performance is required at reasonable cost. Sm–Co is the material of choice when high-temperature stability is required, and Sm–Fe–N magnets are making their way into some niche applications. The scope for improvement in these basic materials by substitution has been rather thoroughly explored, and the effects of processing techniques on the microstructure and hysteresis are largely understood. A big idea from a generation ago—which held real potential to raise the record energy product significantly—was the oriented exchange-spring hard/soft nanocomposite magnet; however, it has proved very difficult to realize. Nevertheless, the field has evolved, and innovation has flourished in other areas. For example, electrical personal transport has progressed from millions of electric bicycles to the point where cars and trucks with electrical drives are becoming mainstream, and looks ready to bring the dominance of the internal combustion engine to an end. As the limitations of particular permanent magnets become clearer, ingenuity and imagination are being used to design around them, and to exploit the available mix of rare earth resources most efficiently. Huge new markets in robotics beckon, and the opportunities offered by additive manufacturing are just beginning to be explored. New methods of increasing magnet stability at elevated temperature are being developed, and integrated multifunctionality of hard magnets with other useful properties is now envisaged. These themes are elaborated here, with various examples.

What Happens after the Rare Earth Crisis: A Systematic Literature Review

Rare earths (REs) play an important role in modern life, and have been the focus of global attention in recent years. As a result, the number of scientific publications has grown enormously, increasing the need for understanding the knowledge base of various research streams and their emerging branches. The economic analysis of REs has also augmented steadily. Nevertheless, the relevant literature is rather fragmented concerning the thematic topics. To respond to this, a systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and a bibliometric analysis were developed to offer a systematic and holistic literature review of the economic research on REs. This review incorporates studies of REs regarding aspects of supply, price, export policy, international trade, relationship with clean energy, and sustainability. The database of this review includes a set of 85 systemically selected state-of-the-art articles from five databases, including Web of Science, Science Direct, Springer, Proquest, and China National Knowledge Infrastructure (CNKI) that were published after the rare earth crisis, covering empirical and theory research conducted in different countries with different resource endowments. The results show that the majority of the economic research studies have been conducted in the past six years. Furthermore, among the six categories, the most popular research trend is sustainability. Some possible opportunities for future research are also illustrated in this paper.

The rapid evolution of speculative investment in the REE market before, during, and after the rare earth crisis of 2010–2012

The purpose of this study is to examine the rate of investment capital that flowed into the rare earth element (REE) junior mining market, to assess the key factors that affected this investment rate, before, during and after the Rare Earth Crisis of 2010–2012, and to determine the result of the total capital invested. The time period chosen for the study was 2006–2015. From the approximately 400 junior mining companies that were pursuing REE during this time period, 28 companies were chosen to represent the market for this study. During the time period, these 28 companies raised a total of $5,924,554,171, with $4,254,272,520 of this amount being raised during the Crisis time period of 2010–2012. Critical factors that affected money flowing into the rare earth junior mining companies were newsletter articles, media coverage, Chinese rare earth policies, government announcements and reports, the initial public offering of Molycorp, Inc., rare earth element prices, World Trade Organization decisions, and junior mining company stock prices. Of the 28 companies, only Lynas Corporation Ltd. and Molycorp, Inc. achieved commercial REE production. Capital flowing into REE junior mining companies declined rapidly from 2013 to 2015, as the market found other solutions and the Crisis subsided.

Sustainability of Permanent Rare Earth Magnet Motors in (H)EV Industry

It is clear that hybrid/electric vehicles [(H)EVs] are only as green as the materials and energy that they use. According to MIT, the production and processing of rare earth elements (REEs) found in (H)EVs come with their own hefty environmental price tag (K. Bourzac, Rare-Earth Crisis, MIT Technol. Rev., 114(3):58–63, 2011). These damages include radioactive wastewater leaks and ‘slash-and-burn processes’ required to manufacture and separate REEs. Some life cycle assessment (LCA) studies found that the carbon advantage of an electric vehicle over an internal combustion engine vehicle is small considering the production/manufacturing and end-of-life stages (C.-W. Yap, China Ends Rare-Earth Minerals Export Quotas, Wall Street Journal, updated 5 Jan. 2015; D.S. Abraham, War Over the Periodic Table, Bloomberg View, 23 Oct. 2015). However, sustainability is not only about environmental impacts, but also concerns other sustainable development principles such as economic viability and social well-being. Permanent magnet (PM) rare earth motors are most widely used in the (H)EV industry, but the price volatility of REEs does not make them an economically sustainable option. The research involving the potential social impacts of the extraction and use of rare earths for the automobile industry is examined. This review addresses the technical aspects of PM motors and how it contributes to or withdraws from the sustainability of (H)EVs. This paper undertakes a review of the literature and the present situation of sustainability of REEs in the electric vehicle industry. Furthermore, this paper highlights the areas of sustainability research considered by academic and industrial representatives to be essential for cleaning up the clean technology. The intention is not to declare rare earth PM motors sustainable, but to analyze their contribution to sustainability in terms of technical, social, environmental, and economic aspects. Ultimately, the potential opportunities toward a more sustainable rare earth PM motor are revealed.

The status of Chinese permanent magnet industry and R&D activities

It has been 15 years since China dominated the rare earth permanent magnet market in 2001. The annual output of sintered Nd-Fe-B magnets in China reached a new record of 126,300 tonnages in 2015 while the output in 2001 is only 6,500 tonnages. The average growth rate from 2001 to 2015 is about 23.5% though the output in 2012 suffers a deep drop due to the well known rare earth crisis in 2011. Currently, the RE magnet production capability in China seems to be over developed compared to actual requirements. Needless to say the oversupply situation implies a hard time for RE magnet manufacturers due to the fierce competition but maybe a good time for the whole industry. The motivation for a company to develop new technology and more competitive products with better performance and/or lower costs is greatly enhanced. The objective of this paper is to give a general picture of Chinese REPM industry and market including the output capability, the status of competition, the development of magnet application and the market trend. Some new research hot points potentially being applied, for example the Cerium magnet, will be introduced as well.

Novel Indicators for the Quantification of Resilience in Critical Material Supply Chains, with a 2010 Rare Earth Crisis Case Study.

We introduce several new resilience metrics for quantifying the resilience of critical material supply chains to disruptions and validate these metrics using the 2010 rare earth element (REE) crisis as a case study. Our method is a novel application of Event Sequence Analysis, supplemented with interviews of actors across the entire supply chain. We discuss resilience mechanisms in quantitative terms–time lags, response speeds, and maximum magnitudes–and in light of cultural differences between Japanese and European corporate practice. This quantification is crucial if resilience is ever to be taken into account in criticality assessments and a step toward determining supply and demand elasticities in the REE supply chain. We find that the REE system showed resilience mainly through substitution and increased non-Chinese primary production, with a distinct role for stockpiling. Overall, annual substitution rates reached 10% of total demand. Non-Chinese primary production ramped up at a speed of 4% of total market volume per year. The compound effect of these mechanisms was that recovery from the 2010 disruption took two years. The supply disruption did not nudge a system toward an appreciable degree of recycling. This finding has important implications for the circular economy concept, indicating that quite a long period of sustained material constraints will be necessary for a production-consumption system to naturally evolve toward a circular configuration.

Framework for resilience in material supply chains, with a case study from the 2010 Rare Earth Crisis.

In 2010, Chinese export restrictions caused the price of the rare earth element neodymium to increase by a factor of 10, only to return to almost normal levels in the following months. This despite the fact that the restrictions were not lifted. The significant price peak shows that this material supply chain was only weakly resistant to a major supply disruption. However, the fact that prices rapidly returned to lower levels implies a certain resilience. With the help of a novel approach, based on resilience theory combined with a material flow analysis (MFA) based representation of the neodymium magnet (NdFeB) supply chain, we show that supply chain resilience is composed of various mechanisms, including (a) resistance, (b) rapidity, and (c) flexibility, that originate from different parts of the supply chain. We make recommendations to improve the capacity of the NdFeB system to deal with future disruptions and discuss potential generalities for the resilience of other material supply chains.

Replacement and Original Magnet Engineering Options (ROMEOs): A European Seventh Framework Project to Develop Advanced Permanent Magnets Without, or with Reduced Use of, Critical Raw Materials

The rare-earth crisis, which peaked in the summer of 2011 with the prices of both light and heavy rare earths soaring to unprecedented levels, brought about the widespread realization that the long-term availability and price stability of rare earths could not be guaranteed. This triggered a rapid response from manufacturers involved in rare earths, as well as governments and national and international funding agencies. In the case of rare-earth-containing permanent magnets, three possibilities were given quick and serious consideration: (I) increased recycling of devices containing rare earths; (II) the search for new, mineable, rare-earth resources beyond those in China; and (III) the development of high-energy-product permanent magnets with little or no rare-earth content used in their manufacture. The Replacement and Original Magnet Engineering Options (ROMEO) project addresses the latter challenge using a two-pronged approach. With its basis on work packages that include materials modeling and advanced characterization, the ROMEO project is an attempt to develop a new class of novel permanent magnets that are free of rare earths. Furthermore, the project aims to minimize rare-earth content, particularly heavy-rare-earth (HRE) content, as much as possible in Nd-Fe-B-type magnets. Success has been achieved on both fronts. In terms of new, rare-earth-free magnets, a Heusler alloy database of 236,945 compounds has been narrowed down to approximately 20 new compounds. Of these compounds, Co2MnTi is expected to be a ferromagnet with a high Curie temperature and a high magnetic moment. Regarding the reduction in the amount of rare earths, and more specifically HREs, major progress is seen in electrophoretic deposition as a method for accurately positioning the HRE on the surface prior to its diffusion into the microstructure. This locally increases the coercivity of the rather small Nd-Fe-B-type magnet, thereby substantially reducing the dependence on the HREs Dy and Tb, two of the most critical raw materials identified by the European Commission. Overall, the ROMEO project has demonstrated that rapid progress can be achieved when experts in a specific area are brought together to focus on a particular challenge. With more than half a year of the ROMEO project remaining, further progress and additional breakthroughs can be expected.