Above: NRC researchers Jean-Michel Lamarre (L) and Fabrice Bernier (R) show the magnet created using the Cold Spray AM technique/Image Credit: National Research Council, Canada
Researchers at National Research Council (NRC) Canada have developed a new 3D printing technology called ‘Cold Spray Additive Manufacturing’ to build high-performance permanent magnets. These magnets are far superior and can be produced at a lower cost. Researchers, Fabrice Bernier and Jean-Michel Lamarre manufactured these new magnets at the NRC laboratory in Quebec. Both the researchers believe that their technique will help develop magnets in complex designs without the need for any sort of assembly.
Cold Spray Process
Cold Spray Additive Manufacturing process involves accelerating the powdered metal particles with a supersonic gas jet and firing them at a substrate layer. On impact, the particles form an atomic fusion bond and build up layer upon layer. The process is controlled with the help of an Industrial robot which performs precise movements to create complex shapes. In comparison to the traditional processes, the cold spray technology is faster.
Above: Lamarre and Bernier observe the cold spray additive manufacturing process at NRC’s cold spray facility/Image Credit: National Research Council, Canada
Why Cold Spray Technique?
Cold Spray technique offers some unprecedented advantages over the traditional processes. Currently, high-performance magnets are produced by traditional manufacturing processes like injection moulding (for bonded magnets) or powder compaction (for sintered magnets). But in these processes, the magnets first need to be manufactured, then shaped as per the design and then finally assembled into the shape. A whole magnet cannot be made in one go. The NRC technology combines all these processes and manufactures the magnet in one single step.
Additionally, the process eliminates the use of binding agents and polymer in the material. This improves the mechanical and conductive properties of the magnet. The magnets show increased thermal conductivity and better oxidation and corrosion resistance.
The process also eliminates the use of glue and assembly, so the magnets have much stronger adhesion properties and are even stronger due to the absence of separable parts. These magnets are also easy to machine as compared to the brittle magnets produced in sintering processes. Cold Spray technique has high build-up rates, it can print several kilograms worth of magnet in an hour.
All the above advantages at a cheaper cost than traditional techniques make cold spray technology the best choice going forward.
What’s Next?
The NRC researchers are now developing soft magnets to complete their range of magnet offerings. Since the world is moving towards clean energy solutions, the next challenge for the researchers will be to develop new ways to augment the electric motors.
According to NRC researcher, Fabrice Bernier, “This technology will allow the creation of more compact, better-performing motors for the future and could pave the way for building entire motors using cold spray technology, offering significant advantages such as cost reduction, better thermal management and more complex geometries and functionalities.”
Researchers believe that this technology will be beneficial in many applications like magnetic cooling, wind turbines, and telecommunications devices.
