If there is one technology field that requires the utmost reliability, it is the space field. Every part of a rocket must work perfectly to protect human lives, especially when operating under extreme conditions, so parts are rigorously tested before humans could be at risk. A recently tested component designed by NASA, is an injector for a rocket engine, but unlock many other components, this one was 3D printed.
Also called additive manufacturing, 3D printing builds an object up, layer by layer, as opposed to starting with a block of material and removing unnecessary pieces. Such subtractive manufacturing though can ensure the finished part is very strong, as it is a single piece, while additive manufacturing may have points of failures at the layers. In this case the component was manufactured using selective laser melting to fuse nickel-chromium alloy powder into the necessary structure. To increase the likelihood of success, NASA designed the component to be comprised of just two parts, compared to comparable injectors made from 115 parts.
When tested, the rocket engine exposed the injector to pressure as high as 1400 pounds per square inch and temperatures reaching almost to 6,000 ºF, but the injector worked perfectly and has shown no sign of failure. Of course more testing is going to be done to confirm how well the printed injector performed, and if it is as successful as is hoped, we may see other rocket components 3D printed, as a means to reduce costs.