The NASA SBIR Phase I funding awarded to Elementum 3D is centered around the development of additively manufactured soft magnetic materials for large diameter
(HETs). In-space electric propulsion systems are growing in terms of importance for interplanetary missions. Better manufacturing methods are needed to produce large diameter Hall-effect thrusters with the right magnetic properties and structural robustness.
Existing magnetic materials and manufacturing methods are inadequate for producing large-diameter Hall-effect thrusters (HETs) with adequate mechanical strength while achieving the desired magnetic properties. Cobalt-iron soft ferromagnetic alloys are desirable for soft magnetic applications, including Hall-effect thrusters, due to their unparalleled magnetic saturation, elevated permeability, high curie temperature, and extreme strength.
Unfortunately, these alloys suffer from manufacturability problems due to low ductility and an inability to produce such alloys in large form factors. While Co-Fe soft magnetic products can be readily produced in sheets, the production of large billets results in weak, brittle, and inhomogeneous materials.
Elementum 3D, in partnership with Altius Space Machines, is proposing to develop an additive manufacturing (AM) process and material feedstock, suitable for the fabrication of large-diameter HETs, from cobalt-iron-based soft magnetic material. The ability for AM to produce these large structures directly from powder feedstock would overcome the unavailability of sufficiently sized iron-cobalt billets. Other AM advantages for the production of Co-Fe soft magnetic products include a favorable fly-to-buy ratio, improved design freedom, and an increase in thrust-to-weight ratio.
The principal objective of the Phase I effort is to research, develop, and demonstrate a soft magnetic feedstock material and additive production process that is suitable for the production of large-diameter Hall-effect thrusters, meeting the magnetic and mechanical performance targets.