来源：X-MOL
Permanent magnets are the fundamental component in the development of modern technology, with their applications extending to fields such as energy generation, transportation, communication, and medical imaging etc. Even though rare-earth transition-metal (RE-TM) intermetallic perform well, rare-earth sources have recently become a bottleneck, and research is being conducted in a number of different ways. To address these gaps, it is essential to explore new approaches to design and manufacture the permanent magnets with non-rare earth materials or reduced content of rare earth elements and with improved energy product. Exchange coupled hard-soft bilayer thin film based permanent magnets have gained significant attention in last couple of decades. The interphase magnetic exchange coupling of soft ferromagnetic phase with hard ferromagnetic phase at the nanoscale leads to a single-phase magnetic behavior that results in enhanced coercivity, remanence, and thus improved high-energy products when compared with the properties of individual phase magnet. Thus, there is renewed interest in this class of permanent magnets because they offer the possibility of reducing the use of expensive and strategically valuable elements. However, the precise control over the thickness of the hard and soft phases of bilayer thin films is essential for effective interphase exchange coupling between them. This work reviews the recent progress made in non-rare earth element-based exchange coupled nanostructured hard-soft permanent magnets, with an in-depth analysis of their magnetic properties and applications.