We love our 3D printers. But sometimes we really wish we could print in metal. While metal printing is still out of reach for most of us, HRL Labs announced a powdered aluminum printing process that they claim is a breakthrough because it allows printing (and welding) of high-strength aluminum alloys that previously were unprintable and unweldable.
The key is treating the metal with special zirconium-based nanoparticles. The nanoparticles act as nucleation sites that allow the aluminum to form the correct microstructure. The full paper on the process appears in Nature.
Other than the nanoparticles, the process is a conventional laser sintered metal powder process. That’s not new. However, aluminum comes in alloys and not all the alloys are good for all purposes. Some of the alloys commonly used for high strength are not weldable and — in general — metal that won’t weld can’t laser sinter, either. HRL claims that 7075 and 6061 are both printable with this process. Presumably, other metals could benefit from this nanoparticle treatment, although different materials may need different kinds of nanoparticles.
We winced at the over-extrusion of the plastic part they show in the video, but hopefully, that was just a stock video. Of course, this isn’t going to make home metal printing affordable. Until that happens, you’ll have to settle for electroplating or you can print with lower-temperature metals.