Good question! There are several reasons. One key reason is that rare earth magnets can produce an equivalent magnetic field with far less volume and mass than copper windings, or even traditional magnets. Both aspects are important in applications like wind turbine generators. In servo applications, these translate into very low moment of inertia for the rotor, which means very high responsiveness.
Another advantage is that no current needs to flow to create the magnetic field, which typically adds a couple percentage points to the efficiency of the motor or generator. In addition, no brushes or slip rings are necessary to get current into the rotor, which saves maintenance. (Yes, I know that induction motors/generators share this.)
While virtually one element controls the world money supply, china who has a larger share of rare earth metals, continue to violate the free trade agreement. 1st by enslaving their citizens, using free trade as an economic weapon whereby their go-betweens close our small family businesses end ecport our manufacturing infrastructure, by erecting slave goods super stores across the world, and 2ndly unfair pricing to close and/or control companies or entire markets. The effects on america have been overwhelmingly devestating, our jobs exported our ports declared free trade zones, 3rdly giving them exploration permits in our geohysical territories, while refusing permits for our own exploration companies, as they control our government through bribery and extortion through their lobbies, and the american arm of the world class mafia, the federal reserve. Our free enterprize system gone, made wealthy the lawyers, judges, politicians, by Nobilities lobbies, while our nation has many slavers: gatses, buffetses, waltonses etc etc, the walton family alone take more than 30 % of our entire workforce (the lowest paid) most of whom work at wallys who have in the last 3 years deflated the walmart avg wage from 12,000 to 10,400 a year. Our current president, who spends his term campaigning, paid for by our tax revenue, works hard to destroy every scientific, and technological asset our nation has--- (proudly claims free trade with korean auto market, when they import more than 12 cars to our country while permitting 1 into theirs) No one discusses the very real globalization and free trade disguised as slavery and the return of virtual Nobility, who have taken our rights, assets, and continue to degrade our quality of life, while smiling, laughing in our faces across all forms of newsmedia, and acdemic cste system they control while taking near 40 % of our nations taxation as interest on money they say they lent us, which is continually stolen by the fedral reserve who refuse audit---3 presidents who tried to oust them were assassinated, Lincoln, Garfield, and Kenedy, Yet if we are to survive as a nation we will have to remove federal reserve, take back the assets they aquired with stolen funds (rockefellers, and relatives rothchilds) have amassed more than 300 trillion in world wide assets from stolen cash from americas cash flow, restore import taxation, resurrect our manufacturing infrastructure, or make what we consume and export to the world, rebuld a military capable of protecting us from the tyrannical hoards that inhabit earth, because we do grow 1/3 of the worlds food supply, and sell it cheaply, or give it away. The time to restore our independent nation is running short under obama et al. While we are administrated by affirmative action, its bizarre
It appears that a big use of the rare earth elements is in permanent magnets for motor and generator fields. Why are wound-field motors and generators so bad? I know it takes a little extra power to excite the field, but you gain the ability to adjust the field strength.
Could someone better versed in motor and generator design please respond?
Right, wrong or indifferent, with the globalization of product design / manufacturing, designers and companies need to take an ever longer term view of key products, materials and technologies to insulate themselves against just such an event. This is not the first, and will not be the last. Uninterrupted supply chain will be the key to long term success, and active strategies that limit the influence of external speculation and influence will become the business normal for the future.
@Rob Spiegel: Molycorp is planning to ramp up rare-earth production by the end of the year. There are insignificant quantities of dysprosium (Dy) and other heavy rare earths at their Mountain Pass deposit in California. The situation is a little better with the Mount Weld deposit in Australia, owned by Lynas Corp ( assuming they can get past the problems of rolling out their separation facility in Malaysia ) - but still, they will not be producing significant amounts of heavies. There are however some promising sources of heavies in Australia, including the Dubbo Zirconia Project owned by Alkane Resources; in the near term we should see some heavies from the Steenkampskraal mine in South Africa, owned by Great Western Minerals. But it will be a number of years until we have significant new quantities online. See www.rareearths.org for info on specific advanced projects that might be of interest.
Technology Metals Research, LLC
While working on a design we always strive to use components and materials that will be widely available throughout the life of a product. It's astonishing to see that we now must not only examine the actual supply, but also examine whether the material will be wildly traded by speculators because it becomes so popular that it has visibility to investors, instead of inventors.
Great article. We all know the effect of speculation in the oil market, but most of us never think about speculation in the rare earth materials market. The fact that neodymium speculation could create such volatility surprises me.
Kristin, thanks for a fascinating article. It was interesting to learn that the price increases were brought about by speculation, rather than the Chinese export limits. I'm looking forward to the rest of the series.
As apresher says, excellent article. This is the type of issue that forces design engineers to adapt an find alternatives. This is a good thing for all. Whether the price increases are due to supply shortages, environmental costs other factors, we are often forced to explore alternatives. Somtimes this efforts leads to better designs.
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