This video shows the additive manufacturing process of a permanent magnet being sprayed onto the interior surface of a cylinder. The process used is called cold spray where a mix of materials in powder form is accelerated to supersonic speeds in gas jet to impact with the surface of a part. The particles undergo a plastic deformation and adhere to the surface. A robot is used to control the deposition of the cold spray into a spiral form that can be later used to create an electric motor.
Video: National Research Council Canada
Read more at 3DPrint.com: http://3dprint.com/201686/magnets-cold-spray-am/