Problem: Do Neodymium Magnets lose its magnetism after being blended??
Result: Confirmed
Explanation: There are three ways for a magnet to lose its magnetism, and the following methods are via heat, demagnetizing its magnetic field, and/or via shock.
- Via heat: Heating up a magnet slightly will cause it to lose some of its magnetism, but on returning to room temperature [depending on how high it was heated, and on the shape of the magnet itself], full magnetism can be restored.
- Via a demagnetizing magnetic field: Permanent magnets exhibit a characteristic called coercivity, which is the ability of a material to withstand being demagnetized by an applied magnetic field. Modern permanent magnet materials such as Sm-Co and Nd-Fe-B have high coercivities; older materials such as Alnico or ceramic [hard ferrite] materials have lower coercivities. With a strong enough magnetic field of opposite polarity, it is therefore possible to demagnetize the magnet [whether this comes from another permanent magnet, or a solenoid].
- Via shock: Shock refers to actions such as being dropped or hit. Loss of magnetism is common among magnets from the olden days. Modern magnets do not face this problem unless sufficient to physically damage the material.
- Conclusion: By blending neodymium magnets, the shock and vibration from being blended is enough for it to lose its magnetism.
Applications for Neodymium Magnets:
- head actuators for computer hard disks
- magnetic resonance imaging (MRI)
- magnetic guitar pickups
- loudspeakers and headphones
- magnetic bearings and couplings
- permanent magnet motors such as: cordless tools, servo motors, lifting and compressor motors, synchronous motors, spindle and stepper motors, electrical power steering and actuators
Credits:
http://www.youtube.com/watch?v=Ax2BOCoVDJk
http://www.physlink.com/Education/askexperts/ae472.cfm
http://www.magnetapplications.com/faq.htm
DMSS June Holiday Physics Assignment 2010 By:
"The Awesome Group" - 3E1 -Claris Pek -Chua Kim Siew -Koh Xing Ying -Mavis Loberas