Radially oriented, anisotropic Nd-Fe-B ring magnets (NEOQUENCH-DR)
Daido has developed a unique hot extrusion process to produce radially oriented anisotropic Nd-Fe-B ring magnets, NEOQUENCH-DR.
- Unlike sintering, this process does not rely on a magnetic field for radial orientation.
- Our process starts with raw material powders manufactured by rapid quenching of the prescribed alloys into nanocrystalline flakes.
- These flakes are hot pressed to the theoretical density and then hot extruded to ring-shaped magnets.
During this advanced hot extrusion process, randomly oriented crystal grains go through preferential grain growth and rotation.
This results in the full-density, nanocrystalline structure with the highest level of radial orientation.
Although the basic magnetic properties (Br, Hc, and (BH)max) are similar to sintered Nd-Fe-B, our unique process gives rise to several remarkable features listed below.
Features of NEOQUENCH-DR
- Highest energy product of 240 ~ 400 kJ/m3 (30 ~ 40 MGOe) in truly radial direction.
- Full rings with a wide range of diameters (min. OD 6 mm -) and lengths (max. 80 mm) for easy assembly.
- Various magnetization patterns possible (multi-pole to uni-pole, various skew angles) by the design of magnetizing fixtures.
- Precise magnetization waveform control (such as rectangular, trapezoidal, sinusoidal) for high power or low cogging.
- High heat resistant grades (up to 180 deg.C) available.
- Inherently better corrosion resistance due to the absence of internal porosity.
Applications of NEOQUENCH-DR
- EPS (Electric Power Steering) motors: Combined with controlled magnetization waveforms, NEOQUENCH-DR can realize quiet and smooth rotation, giving rise to a natural feeling of steering an automobile.
Servomotors: High power and low cogging, quiet and smooth rotation, ideal for AC/DC servomotors used in industrial robots requiring quick and accurate movements.
Manufacturing process of NEOQUENCH-DR
Realizing close theoritical density and high radial orientation ratio by hot extrusion technology keeping miro structure of grain size.