The research team has overcome key challenges, achieving another significant improvement in the performance of NdFeB magnets.

Recently, a research team jointly established by the School of Materials Science and Engineering at Tsinghua University and China Northern Rare Earth announced a breakthrough in the field of optimizing the performance of NdFeB magnets, successfully addressing the industry-wide challenge of insufficient high-temperature stability of these magnets. The relevant technological achievements have passed certification by the National New Materials Testing Center.

According to the team leader, this research focused on the pain point of magnetic performance degradation in NdFeB magnets under high-temperature conditions above 200℃. By innovating a "dual-phase nanocomposite" preparation process, a uniformly distributed rare earth-transition metal compound interfacial layer was constructed within the magnet. This raised the Curie temperature of the magnet to 385℃, representing a 22% increase compared to traditional products. Under a working environment of 220℃, the temperature coefficient of remanence was optimized from -0.12%/℃ to -0.08%/℃, resulting in a 33% reduction in the rate of magnetic performance degradation.

This technological breakthrough was achieved after 23 months of dedicated research, involving a cumulative total of 127 sets of comparative experiments. Test data showed that while maintaining a magnetic energy product of 55 MGOe, the high-temperature coercivity of the new magnet exceeded 3200 kA/m, setting a new global record for similar products. Currently, 17 invention patents have been applied for in relation to this technology, with 8 already granted.

"This breakthrough will directly promote the application of NdFeB magnets in extreme environments such as aerospace engines and deep-sea exploration equipment," commented an expert from the Chinese Society of Rare Earths. China Northern Rare Earth has initiated the construction of a pilot production line with an annual capacity of 500 tons and expects to achieve mass production by 2025. This will reduce the cost of core materials for China's high-end equipment manufacturing industry by approximately 18%.

Industry analysts pointed out that this achievement has propelled China into the global forefront in terms of the high-temperature performance of rare earth permanent magnet materials and will accelerate the upgrading and iteration of products such as drive motors for new energy vehicles and industrial-grade servo systems.