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REEs are a series of chemical elements found in the Earth’s crust that are essential components of many technologies, including electronics, computer and communication systems, transportation, health care, and national defense. Rare Earths Elements (REE) are incorporated into many sophisticated technologies with both commercial and defense applications including smartphones and flatscreen televisions to hybrid cars, wind-turbine power systems to communications equipment. These are referred to as “rare” because although relatively abundant in total quantity, they appear in low concentrations in the earth’s crust and extraction and processing is both difficult and costly.
The top rare earth producing countries are China (105,000 tons), Australia (10,000 tons), US(4,100 tons), Russia(2,500 tons), Thailand(1,100 tons) and Malaysia (200 tons). Some estimates are that China now produces about 90- 95% of the world’s rare earth oxides and is the majority producer of the world’s two strongest magnets, samarium cobalt (SmCo) and neodymium iron boron (NeFeB) permanent, rare earth magnet. The 70% of the world’s light rare earths coming from a single mining operation at the Bayan Obo deposit in Inner Mongolia.China imposes several different types of unfair export restraints on the materials at issue in today’s consultations request, including export duties, export quotas, export pricing requirements as well as related export procedures and requirements.
Rare earth elements consist of 17 elements on the periodic table, including 15 elements beginning with atomic number 57 (lanthanum) and extending through number 71 (lutetium), as well as two other elements having similar properties (yttrium and scandium). Rare earths are divided into two groups: light rare earth elements (LREE) – lanthanum, cerium, praseodymium, neodymium, promethium, and samarium, and heavy rare earth elements (HREE) – europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, scandium, and yttrium.
One of the mitigation strategy being pursued by countries is to look for alternatives to rare earth minerals
New Alternatives May Ease Demand For Scarce Rare-Earth Permanent Magnets
Now, scientists have identified magnets based on more readily obtainable rare earths, as well as some promising magnets that don’t contain these materials at all. We have developed new ways to better predict which materials make good magnets,” says Thomas Lograsso, Ph.D., who led the team. “Experimentally, we can ‘rehabilitate’ near-magnet systems, called paramagnets. We start with alloys or compounds that have all the right properties to be ferromagnetic at room temperature. Many times, these materials have high proportions of iron or cobalt.”
Paramagnets are materials that are weakly attracted to a magnetic field and are not permanently magnetized. But by adding alloys, paramagnets have been transformed into ferromagnets, or regular permanent magnets, like the metal surface of a refrigerator. Lograsso’s team at the Critical Materials Institute at Ames Laboratory has identified two promising candidates thus far using this “rehabilitative” approach, and both are forms of cerium cobalt: CeCo3 and CeCo5. Although cerium is called a rare-earth element, it is very abundant and easy to obtain.
Magnetic nanoparticles that could offer alternative to rare Earth magnets synthesized
A team of scientists at Virginia Commonwealth University has synthesized a powerful new magnetic material that could reduce the dependence of the United States and other nations on rare earth elements produced by China. The new material consists of nanoparticles containing iron, cobalt and carbon atoms with a magnetic domain size of roughly 5 nanometers. It can store information up to 790 kelvins with thermal and time-stable, long-range magnetic order, which could have a potential impact for data storage application. When collected in powders, the material exhibits magnetic properties that rival those of permanent magnets that generally contain rare earth elements.
Permanent magnets, specifically those containing rare earth metals, are an important component used by the electronics, communications and automobile industries, as well as in radars and other applications.Additionally, the emergence of green technology markets — such as hybrid and electric vehicles, direct drive wind turbine power systems and energy storage systems — have created an increased demand for permanent magnets.
“The discovery opens the pathway to systematically improving the new material to outperform the current permanent magnets,” said Shiv Khanna, Ph.D., a commonwealth professor in the Department of Physics in the College of Humanities and Sciences.New metal alloy could yield green cooling technologies, RIT scientist explores alternatives to rare-earth magnetsA promising new metal alloy system could lead to commercially viable magnetic refrigerants and environmentally friendly cooling technologies, according to Casey Miller, head of RIT’s materials science and engineering program.
The materials use magnetic fields to change a refrigerant’s temperature without the coolant gases associated with global warming. The thermodynamic phenomenon, called “magnetocaloric effect,” makes magnetic refrigeration an environmentally friendly and efficient alternative to current cooling technologies.The alloy is a substitute for metals made from rare-earth elements, predominantly produced in China and increasingly used in modern magnets .Transition metals typically offer supply chain stability and are cheaper by weight than rare-earths, they said.
“Our work is a great example of President Obama’s Materials Genome Initiative in action,” Miller said. “We created alloys containing four and five different elements whose properties helped our theory collaborators develop a calculation that predicts the magnetic properties of a larger set of compounds that have not yet been synthesized. Now we have identified hundreds of new alloy combinations that could be useful.”
Miller and his colleagues investigated the family of metal compounds known as “high entropy alloys.” This class of emergent materials holds potential for advanced manufacturing and possess hardness and resistance to wear and corrosion, the authors found.
