Powertrain & Energy - July 25, 2012 - 24

The
row about
earths
rare
Dysprosium,
another crucial
rare-earth
ingredient of
permanent
magnets,
skyrocketed from
$100/kg to $3400/
kg in three years.
(Arnold Magnetic
Technologies)
Avalon Rare Earth’s Nechalacho mine in Canada.
Japan, which accounts for a third of global REE demand, now
provides subsidies for recycling and investment in new ways to
cut usage. Honda, for instance, just said that it would start recycling
rare earths from used car parts such as the nickel-metalhydride
batteries used in hybrid cars, which contain small
amounts of neodymium along with lanthanum and cerium.
Many companies in the meantime delayed product rollouts
and strove to find alternative suppliers and technologies.
“Engineers looked to find ways around the problem,”
Constantinides said, “dropping motor temperatures or adopting
approaches that use less-strong magnets, such as ferrites. Or
they avoided permanent magnets altogether like Tesla did
with his induction motors.” Induction motors use magnetic
fields generated by an electrical current to drive the rotor.
Toyota reported in 2011, for example, that it was developing
induction motors that would not require RE magnets, but
motor researchers at Oak Ridge National Laboratory and
elsewhere say that induction motors will never be as efficient
as permanent magnet types. More recently, spokesmen for the
24 July 25, 2012
Japanese automaker said that it has “developed
a way to make hybrid and electric
vehicles without the use of expensive
rare earth metals” and “could bring the
technology to market in two years if the
price of rare earths does not come
down.”
Hitachi just announced that its engineers
have designed an 11-kW prototype
motor sans REEs, the result of four
years of engineering work. The new
Hitachi motor is expected to enter commercial
production in 2014.
Elsewhere, scientists are exploring
how to reduce the amount of dysprosium
in magnets by placing dysprosium
only at the boundaries between the
magnet grains. Researchers in Japan at
the University of Tohoku and
Intermetallics Co. Ltd., as well as
SAE Powertrain & Energy
Powertrain & Energy - July 25, 2012

Table of Contents for the Digital Edition of Powertrain & Energy - July 25, 2012
