Rocket Engine Component 3D Printed in One Piece

This aluminum rocket engine, which uses liquid oxygen as a propellant, is an example of design and process consolidation made possible through additive manufacturing. The 3D printed rocket engine was made completely in one piece, no postprocess machining required. We spotted this part (and filmed the video above) at Formnext 2024 in Frankfurt, Germany.

The 1,300-mm tall rocket engine was produced through laser powder bed fusion on a four-laser machine from Eplus3D, which features four 500-watt lasers and a build size of 1,600-mm. The printing process lasted over 354 hours at a layer height of 60 micron. A fine layer height was essential to fulfilling the resolution requirements for many of the rocket engine’s features, notably, its internal channels. In operation, these channels use the cryogenically cooled propellant as a coolant circulating it through the housing of the engine. 

Using an AI-enabled computational tool from software company Leap 71, the rocket engine was produced through generative design. Operational constraints and requirements were inputted in terms of the performance needed from the engine, enabling Leap 71’s software to create the design using iteration. One of the engine’s geometrical constraints served additive manufacturing, ensuring each overhang feature was positioned at an angle where zero support structures would be necessary. No support structures meant that no features had to be removed, enabling the rocket engine to be produced entirely without postprocessing.

Related Resources

• The Cool Parts Show episode featuring a lightweight combustion chamber for a 3D printed engine, developed by Masten Space Systems, now part of Astrobotic’s Propulsion & Test department.
• The Cool Parts Show episode highlighting NASA’s 3D printed thrust chamber assembly.
• The Cool Parts Show episode about a 3D printed rocket fuel injector from Fabrisonic for TGV Rockets & Propulsion Systems.
• A playlist of other videos from Formnext 2024. 
• All of our materials regarding additive manufacturing for spacecraft and rocket propulsion.

Transcript

Peter Zelinski

The key to realizing the promise of additive manufacturing is design consolidation, process consolidation. Here is a radical example of both.

Pete Zelinski, Additive Manufacturing Media. I'm at the Formnext expo in Frankfurt, Germany. This rocket engine was made in one piece. In one step, 3D printed entirely in one piece. No postprocessing required, finished out of the 3D printer.

So, it was made through laser powder fusion on a machine from Eplus3D. Four-laser machine, four 500-watt lasers. A machine with a build size of 1,600 mm. This part is 1,300 mm tall, made of aluminum. It is for a rocket engine that uses liquid oxygen as a propellant.

So, printing this part took 354 hours at a layer height of 60 micron, a relatively fine layer height because of the resolution required in some of these features. Notably, these internal channels that use the cryogenically cooled propellant as a coolant, circulating it through the housing of the engine.

The design work was consolidated as well. There was not a lot of CAD work that went into this. Leap 71 developed the AI-enabled computational tool that produced this model through generative design. So, requirements were input in terms of the performance needed from the engine. Operational constraints were input and the Leap 71 software arrived at this design through iteration.

One of the geometric constraints served additive manufacturing, and it had to do with making sure that every overhang feature was at an angle such that no support structures would be needed, no support structures anywhere.

You can see, for example, in the ramp of these internal channels or the way these holes at the bottom, the vertical ones are circular, but the one that's on the side is diamond shaped. All to ensure no support structures, meaning no features had to be removed, meaning no post-processing after this part is 3D printed.

We've done other pieces on additive manufacturing for spacecraft and rocket propulsion in particular. Find links in the description.