Text: Eric Tipan / Photos: Honda | posted July 14, 2016 10:08
New magnet will have no rare earth metal
Honda Motor Company Ltd. along with Daido Steel Company have co-developed a new neodymium magnet with high heat resistance properties without the need for rare earth metals that will be used in the all-new Honda Freed and future hybrid vehicles.
This new development will make the drive motors in electric vehicles cheaper to make because these new hot deformed neodymium magnet contain no heavy rare earth, which as the name suggests come only in very limited quantities in any part of the world and are very costly to procure.
Neodymium magnets are utilized in drive motors of electric and hybrid vehicles because of their high heat resistance and high magnetic force. As the motoring industry shifts towards the use of alternative fuel, the demand for neodymium magnets will grow exponentially.
To make these magnets highly heat resistant, rare earth metals like dysprosium and/or terbium are used. However, these metals are highly scarce and expensive, which in turn increases the cost of EV and hybrid production.
The challenge to reduce the use of heavy rare earth metals and the cost of drive motors production has been met by Honda and Daido Steel by mass-producing neodymium magnets using the hot deformation method.
This method of neodymium magnet production enables nanometer-scale crystal grains to be aligned to realize a fine crystal grain structure that is approximately ten times smaller than that of a sintered magnet, which makes it possible to produce magnets with greater heat resistance properties.
Honda revised the shape of the magnet to make it fit in the drive motor of its hybrid vehicles while also redesigning the motor and the shape of the rotor to optimize the flow of the magnetic flux of the magnet.
The result is a hot deformed neodymium magnet with no heavy rare earth metal that provides torque and with heat resistance performance similar to a conventional magnet.
Honda will use the new hot deformed neodymium magnet on the Honda SPORT HYBRID i-DCD 2 system for the all-new FREED.