Georgia Institute of Technology Materials Science and Engineering

Metal 3D printing has the potential to reduce reliance on supply chains and bring operational autonomyto remote locations. However, due to stability and power demands, metal 3D printing has traditionally been restricted to well-controlled facilities. With support from NASA as well as the GTRI HIVES program, the Kacher Lab is developing new methods for robust metal 3D printing, capable of operating from locations ranging from forward operating bases to the moon.

The most commonly used metal 3D printing techniques employ high powered lasers to melt metal powders in desired patterns, resulting in a net-shape metal component. The high power requirements of the laser, difficulties working with metal powders, and stability needed during operation all make this standard approach difficult to apply in remote environments. The Kacher Lab instead uses metal oxide powders embedded in a polymer binder as the starting point. This ‘ink’ is then printed using a standard, extrusion-based printer, such as are often used for printing polymers. Once printed, the part is loaded into a hydrogen furnace where the binder is burned away and the oxides particles are sintered and reduced, resulting in a metal component. The oxide powders are highly stable and often readily available, and the extrusion-based printing has minimal environmental and energy requirements. To date, the Kacher Lab has demonstrated the ability to print pure metals, such as iron, nickel, and molybdenum, as well as alloys such as high entropy alloy (FeNiCoCrMn), steels, and cobalt chromium.

This approach to 3D printing has far reaching applications in printing metal parts in remote environments. As we work towards establishing a permanent human presence on the moon, manufacturing parts for repair, replacement, or innovation will be vital as the cost to ship parts is so high. Closer to home, supply chain issues are an ever present reality for forward operating bases, where even simple issues can take months to resolve as parts are located and shipped. The ability to rapidly manufacture parts in these remote environments could cut down significantly on our reliance on supply chains and increase operational efficiency at these remote locations.