NdFeB Magnet Grain Boundary Diffusion Technology
Breakthrough in NdFeB Alloy Diffusion Process
The GBD alloy diffusion process achieves significant performance improvements in NdFeB magnets through innovative material design and precise process control. Using Dy/Tb-Fe based alloys as diffusion sources, the optimized composition (e.g., 5-10% Al/Cu additives) forms a low-melting eutectic phase during 900-950°C heat treatment, greatly enhancing diffusion efficiency. Experimental results show:
Diffusion depth exceeds 500μm
10-20nm (Nd,Dy)₂Fe₁₄B strengthening layer forms on grain surfaces
Coercivity increases by 40-60% with only 3-5% remanence loss
Resource Efficiency & Industrial Applications
Grain Boundary Diffusion process reduces heavy rare earth usage by 50-70%, cutting content from 3-5wt% to 1-2wt%. Industrial applications demonstrate:
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Screen-printed alloy paste enables batch production (ΔHcj<5%)
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Saves 30g Dy/Tb per EV motor, reducing costs by 15%
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Future Dy/Tb-Al-Cu alloys may further lower usage to <0.8wt%
