Cold Spray Additive Manufacturing Fabrication of Hard and Soft Magnetic Materials

Manufacturing increasingly complex parts featuring advanced functionalities while reducing costs is a challenge for all industries. Automotive electric motor fabrication is no exception as high performance magnetic materials need to be shaped and installed into complex assemblies. Current fabrication procedures severely limit the design flexibility as magnetic materials are typically difficult to machine and manipulate. In this work, we will describe the use of cold spray additive manufacturing for the low-cost direct shaping of hard and soft magnetic materials on electric motor parts without the need for additional assembly steps. Combination of sprayed soft and hard magnetic materials opens up the possibilities for innovative designs leading to performance gain and cost savings. The role of the process parameters such as the gas temperature as well as the powder composition, size distribution and morphology on the magnetic properties is discussed. The use of robot toolpath programming necessary to spray on motor parts is illustrated by different examples of complex shape prototypes. Use of soft and hard magnetic materials for the realization of motor prototypes is shown, thus demonstrating the feasibility of using cold spray additive manufacturing as an effective technology to fabricate motor parts.