3-D printed rocket engine prototype
NASA tested first 3-D printed rocket engine prototype part made of two different metal alloys through an advanced manufacturing process. NASA makes and evaluating durable 3-D printed rocket parts made of one metal. But, the technique of 3-D printing with more than one metal is more difficult.
It is a technological achievement to 3-D print and test rocket components made with two different alloys,” said Preston Jones, director of the Engineering Directorate at Marshall. This process reduces future rocket engine costs by up to a third and manufacturing time by 50 percent.
Engineers tested low-pressure hot-fire prototype more than 30 times to demonstrate the functionality of the igniter. The prototype, built by a commercial vendor. The results showed the two metals had inter-diffused, a phenomenon that helps create a strong bond.
A rocket engine igniter used to initiate an engine’s start sequence. In traditional manufacturing, igniters used a process called brazing which joins two types of metals by melting a filler metal into a joint creating a bi-metallic component. The brazing process requires a significant amount of manual labor leading to higher costs and longer manufacturing time.
By diffusing the two materials together through this process, a bond is generated internally with the two materials and any hard transition is eliminated that could cause the component to crack under the enormous forces and temperature gradient of space travel.
hybrid 3-D printing process
For igniter prototype, the two metals, a copper alloy and Inconel, join together using a unique hybrid 3-D printing process called automated blown powder laser deposition. The prototype igniter made as one single part instead of four distinct parts. This bi-metallic part created during a single build process by using a hybrid machine. The machine integrated 3-D printing and computer numerical-control machining capabilities to make the prototype igniter.
While the igniter is a relatively small component at only 10 inches tall and 7 inches at its widest diameter. This new technology allows much larger part to make and enables the part’s interior to be machined during manufacturing. The hybrid process can freely alternate between freeform 3-D printing and machining within the part before the exterior finished and closed off.
This new advanced manufacturing technology could do for the Space Launch System program in the future, researchers said. In next generation rocket engines, we aspire to create larger, more complex flight components through 3-D printing techniques.
More information: [NASA]