LMDR utilizes a focused laser beam to introduce controlled thermal shocks onto the surface of the electrical steel. These thermal shocks create new magnetic domain walls within the material, effectively refining the size and distribution of existing magnetic domains.
This refinement brings several benefits for reducing core loss:
1. Reduced Domain Wall Movement: Smaller domains experience less “sticking” during magnetization and demagnetization cycles, leading to lower hysteresis loss.
2. Minimized Domain Wall Oscillations: Smaller domains have higher resonance frequencies, making them less susceptible to vibrations caused by the changing magnetic field. This reduces energy dissipated by domain wall oscillations, contributing to lower eddy current loss.
3. Optimized Domain Patterns: The controlled introduction of domain walls through LMDR allows for fine-tuning the direction and distribution of domains within the material. This can further optimize energy transfer paths and minimize overall core loss.
Loss Reduction Potential:
LMDR can typically achieve loss reductions in the range of 5% to 15%, depending on the specific steel grade, frequency, and applied processing parameters. While this might appear smaller compared to the LMDR technology we discussed earlier, it’s important to note that LMDR also offers several advantages:
- Lower processing cost: LMDR is a relatively quick and non-invasive process compared to microstructural modification techniques.
- Scalability: LMDR can be readily implemented on existing production lines with minimal disruption.
- Compatibility with existing steel grades: LMDR can be applied to various commercially available electrical steel grades without significantly altering their magnetic properties.
Overall, LMDR presents a valuable tool for incrementally reducing core loss in electrical steel while offering practical advantages for implementation and compatibility. It complements and potentially works in conjunction with microstructural modification techniques like the LMDR I previously described, paving the way for even greater efficiency gains in the future.