A Low Cost Continuous Process to Produce Magnet Alloys

The current processes to produce Nd-Fe-B alloy powders for producing high magnetic strength permanent magnets for application in electric traction motors for use in electric vehicles requires a significant number of steps resulting in high cost. To meet the cost goals for these motors to expand the availability of electric vehicles, substantial reductions in cost to produce the Nd-Fe-B alloy powders must be achieved. Starting from the rare earth oxide Nd2O3 it is possible to produce the alloy Nd2Fe14B which is the highest magnetic strength composition utilizing similar processing that has been demonstrated to produce high purity low cost titanium alloy powder. A chloride base process utilizes a carbothermically treated oxide to produce an intermediate that fully chlorinates to produce NdCl3 that when combined with FeCl2 and BCl3 can be metallothermically reduced to the alloy powder Nd2Fe14B with a byproduct metal chloride that is readily vacuum separated at a low temperature for recycle to produce the reductant and chlorine for making NdCl3. The only off gas is CO2 as all other reactants are recycled leading to a continuous process to produce high purity Nd2Fe14B alloy powder at low cost. Commercial Applications and Other Benefits: Substantially reducing the cost and energy in an environmentally friendly process to produce low cost Nd2Fe14B alloy powder provides the material to produce high quality permanent magnets at low cost that translates to producing more electric vehicles. The greater use of electric vehicles reduces pollution, reduces the need for oil/petroleum and the attendant advantages of reduced importing of oil. A greater use of electric vehicles emanating from low cost permanent magnets is a benefit to the entire Nation. The low cost Nb2Fe14B is also applicable for magnets for wind generation of electricity.