NASA has started to 3D Print a combustion chamber liner using selective laser melting 3D printers which is expected to operate at extreme temperatures.
A material called GRCo-84, a copper alloy manufactured at Glenn Research Center in Ohio is utilized whilst 3D printing the combustion chamber liner. The liner is the result of 8,255 3D printed layers of the alloy, which is carefully sintered layer by layer to create the functioning liner. According to a press release by NASA, the whole 3D printing process takes approximately 258 hours.
Despite the unexpectedly slow 3D printing process, Zach Jones, the Materials Engineer of NASA states that “Copper is extremely good at conducting heat. That’s why copper is an ideal material for lining an engine combustion chamber and for other parts as well, but this property makes additive manufacturing of copper challenging because the laser has difficulty continuously melting the copper.” For the rocket to endure through the extreme temperatures in the outer space, copper must be used to create the chamber liner and therefore, such “sluggish” process is needed.
The Associate Administrator for the Space Technology Mission Directorate at NASA Headquarters stated that building of a full scale copper rocket parts with additive manufacturing is a breakthrough for Aerospace 3D Printing, and that it will frequently be used in the near future to 3D print other parts of the rocket.
Although copper alloy takes a much longer time than other materials to be melted, copper is one of the only substance which can last “the mixture of extremely cold propellants which are then heated to extreme temperatures on the other end of the spectrum.”