Part of the reason for the continued elevation is the growth in real demand. Perhaps more importantly, suppliers around the globe, including those in China, face more stringent environmental constraints than they did even a few years ago, and mitigation techniques cost money.
Its very likely that the base prices for rare earth materials coming from China will be permanently higher than they used to be because of the necessary inclusion of capital expenditure associated with environmental cleanup, Hatch says.
Solving the rare earth challenge
There's another bit of good news out there, though. There are design techniques that can minimize the effect of rare earth pricing. Those methods were responsible for the demand reduction last fall that started the price slip. Motor designers can minimize the impact of elevated pricing using four basic approaches:
- Optimizing the composition and amount of rare earth magnets used
- Minimizing the amount of rare earth materials in the magnets
- Avoiding the use of rare earth magnets
- Eliminating magnets entirely
The right technique depends on the application. Using a low-grade neodymium magnet with less dysprosium might yield a dramatic price decrease, but if the motor has to be used in glass manufacturing or iron smelting, avoiding dysprosium may not be an option.
In Part 2 of this five-part Design News series, we'll look at how focusing torque in three dimensions can deliver ferrite magnet motors with form factors near those of comparable rare earth versions.