The 2-Powder Method (2PM) is an innovative powder metallurgy process developed to produce high-performance NdFeB sintered permanent magnets while significantly reducing the use of critical heavy rare-earth elements (HREEs) such as dysprosium (Dy) and terbium (Tb). These magnets are essential components in a wide range of strategic technologies, including electric vehicle traction motors, wind turbine generators, robotics, automation systems, medical devices, digital infrastructure, defense equipment, and consumer electronics. By reducing dependence on scarce and geopolitically sensitive raw materials, the innovation contributes directly to improving supply security, sustainability, and the technological sovereignty of Europe.

The primary objective of the 2PM process is to maintain or improve the magnetic performance and temperature stability of NdFeB magnets while dramatically reducing HREE consumption. This is particularly important for applications operating at elevated temperatures, such as electric vehicle motors, where Dy and Tb are traditionally added to improve coercivity and thermal stability. However, these elements are among the most critical and expensive rare-earth materials in the world, with supply chains heavily concentrated in a limited number of countries.

The innovation is based on blending two NdFeB powders with different compositions and particle sizes. The first powder is free of heavy rare-earth elements and consists of relatively coarse particles. The second powder contains Dy or Tb and is significantly finer. During conventional powder metallurgy processing, including magnetic alignment, compaction, and sintering, the finer HREE-containing particles melt earlier and distribute around the larger HREE-free particles. This results in the formation of a unique core-shell microstructure. In this structure, HREEs are concentrated only in the outer shell regions of the magnetic grains, while the grain cores remain free of these critical elements.

This microstructural design is highly efficient because magnetic reversal processes originate at the grain boundaries rather than in the grain centers. Consequently, only a thin HREE-enriched shell is required to increase coercivity and temperature stability. The innovation therefore achieves equivalent or improved magnetic performance while using significantly lower quantities of expensive and critical heavy rare-earth elements.

A key strength of the technology is its compatibility with existing industrial manufacturing methods. The process uses the standard powder metallurgy route already employed for NdFeB magnet production, including strip casting, hydrogen decrepitation, jet milling, powder alignment, pressing, sintering, and post-sinter annealing. The only additional step is the blending of the two powders. This makes implementation straightforward and minimizes investment requirements for manufacturers. Furthermore, unlike the widely used Grain Boundary Diffusion Process (GBDP), the 2PM process has no practical limitations related to magnet thickness and does not require additional coating operations, diffusion heat treatments, or extra finishing steps.

Technical feasibility has already been demonstrated on the pilot production line at Fraunhofer IWKS in Germany, where large magnets weighing approximately 350 grams have been successfully produced with homogeneous core-shell structures throughout the full volume of the component. The technology has reached Technology Readiness Level (TRL) 8, confirming its readiness for industrial scale-up.

The sustainability benefits are significant. Life Cycle Assessment studies show that the 2PM process produces at least 8% lower CO₂-equivalent emissions compared with alternative rare-earth-saving technologies such as Grain Boundary Diffusion Processing. The process also reduces consumption of critical raw materials, decreases waste generation, and simplifies production.

Originally patented by the Technical University of Darmstadt, the technology has been further developed through collaboration with Fraunhofer IWKS and supported by the German Federal Ministry of Education and Research. Additional patent protection has been secured for recent improvements.

Overall, the 2-Powder Method represents a major innovation in permanent magnet manufacturing. By combining conventional powder metallurgy with intelligent microstructural engineering, it delivers high-performance magnets with lower rare-earth consumption, reduced environmental impact, lower production costs, and improved supply-chain resilience, making it a highly attractive solution for the next generation of energy, mobility, and industrial technologies.