Neodymium-Iron-Boron Permanent Magnets
Ames Laboratory scientists have come up with a new process to prepare neodymium-iron-boron (Nd2Fe14B) permanent
magnets that has the potential to enable them to be produced economically in the United States. What's more, the Ames Laboratory
process doesn't produce the environmentally unfriendly byproducts that result from traditional manufacturing methods.
The Most Powerful Magnets in the World
"Neodymium-iron-boron magnets represent perhaps one of the most important uses of rare-earth elements," says Karl Gschneidner Jr.,
senior metallurgist at Ames Lab, who co-developed the process along with Rick Schmidt, principal scientist emeritus. "They're the
most powerful magnets in the world." And they can be found in every computer and every hybrid and electric vehicle that rolls off
an assembly line as well as a wide array of consumer, commercial and military products.
The Rare Earth Magnet Industry Moved to China
Little wonder. Permanent magnets make up a $4.1 billion global industry. Over the years, however, production of neodymium- based
magnets has shifted to China and other low-cost-producing nations. The hope is that the new technology will help U.S.-based companies
compete with these other nations on an economic basis.
The Schmidt-Gschneidner process leveraged know-how that had been amassed at the Ames Laboratory for more than half a century. Early
lessons learned from the Lab's World War II role processing uranium were put to use by scientists researching rare earths. As
breakthroughs at the Lab continued over the years, the scientific community began to view the Ames' facility as "one of the best
places to be if you're researching rare earths," Gschneidner says. Now, fast forward to the early 1980s, when the discovery of
Nd2Fe14B magnets by U.S. and Japanese researchers set off a renewed flurry of related research at the Ames Lab and elsewhere.
Owing to their unique advantages of strength and durability, manufacturers began incorporating Nd2Fe14B magnets into more and more products.
The unfortunate tradeoff was an increase in the amount of unhealthy waste materials created as ever-larger amounts of neodymium for the magnets was being processed.
Indeed, the conventional refining process starts with the neodymium oxide, but goes through two steps in order to obtain the
neodymium metal. Waste products are associated with both these steps, and they must be handled in an environmentally friendly manner.
A One-Step Process for Refining Neodymium
In 2009, Ames Laboratory researchers began work on a greener process for refining neodymium. Instead of two steps, "it is a one-step
process going from the neodymium oxide to the neodymium master alloy," Gschneidner explains, "and since the end-products are completely
utilized, there are no waste materials to dispose of."
Bringing the Magnet Industry Back to the US
A green process with the potential to bring a greater share of the permanent magnet industry back to U.S. shores represents a major
achievement in itself. But the greatest long-term benefit of the Ames Lab process may be yet to come. Gschneidner believes that
"a modification of this process should enable us to prepare a lanthanum [element 57 on the periodic table] master alloy to produce
lanthanum-nickel-metal hydride batteries, which are used in hybrid and electric vehicles."
A cheaper, greener battery for the world's growing fleet of hybrid vehicles could eliminate untold tons of carbon dioxide, and it's
just the kind of industry needed to help ensure America's economic health for decades to come.
|Producing high strength magnets - such as this neodymium-iron-boron magnet - is one of the most important uses of rare earth elements. Photo by Ames Laboratory, United States Department of Energy.
|Rare Earth Elements in the News