The ability to print multiple materials at the same time is a step change in the capability of 3D printing that will propel it faster into mainstream manufacture.
Advances in 3D printing have been slow to replace traditional manufacturing, but NASA is looking toward the technology as a way to fabricate parts for rockets. It’s already experimented with rocket components that were 3D printed from a single metal, but now it’s testing a process for printing in two different alloys. Using an advanced laser printing method, the agency has produced a bi-metallic rocket igniter that really works.
As the name implies, a rocket igniter is used to initiate a rocket engine’s start sequence. It’s a surprisingly complex part that’s difficult to make, so it’s an ideal candidate for 3D printing. However, you can’t make a rocket igniter out of a single metal. In traditional manufacturing, these components are produced using a process called brazing. The two different metal components are melded together using a filler material that locks them into place when the component is heated.