Terbium-iron alloys magnetostriction

Silvery metal, that can be cut with a knife. Terbium alloys and additives are widely used in optoelectronics to burn CDs as well as in laser printers. The pronounced magnetostriction (Joule effect) makes "terfenol-D" (terbium-dysprosium-iron) indispensable in sonar technology. The physics of the element appears to be more interesting than its chemistry, in which it is rarely used in catalysis. 

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