PermiAM is a patented technology for laser powder bed fusion (LPBF) additive manufacturing (AM) which enables printing of porous material with controllable permeability together with fully dense material.
The process allows for easy integration of precise permeability for control of pressure and flow for applications such as fuel injection, rocket and combustion engines, wicking heat pipes, transpiration cooling, filtration, catalysis, and more. The methods allow for process-based generation of the permeable regions from a simple CAD model without the need for complex CAD modeled microporous structures.
The technology was initially matured by Elementum 3D and Masten Space Systems (now Astrobotic) with support from a NASA SBIR program. The ability to integrate regions with controlled permeability with solid material in printed parts can improve performance and reliability while simplifying manufacturing for reducing cost and time.
The innovative process introduces the capability to engineer materials with open porosity of a smaller scale than is traditionally possible in CAD-based AM methods. The technology is applicable for printable metal alloys including aluminums, superalloys, coppers, steels, and refractories. Porosity can be graded across the geometry enabling precisely tuned permeability across a region.
PermiAM for rocketry and propulsion has been described as ‘game changing’ by industry experts. During a 65 second hot fire test and a combustion temperature of 6100°F, the temperature of the PermiAM injector face remained at only 380°F after 125 seconds of operation time with zero face erosion or damage. More than 800 seconds of successful hot fire testing across multiple material sets were accumulated during the NASA SBIR project. In addition to the performance and capability gains, PermiAM enabled a 60% manufacturing cost savings for the fuel injectors as well as 92% faster lead time.
