Finding the flow creates a new way to 3D-print metal

 Eric Mack


Direct metal writing uses semi-solid heated metals forced through a 3D printer nozzle (Credit:Lawrence Livermore National Lab)


A team of engineers has developed a new way of 3D-printing metals that could improve on existing, laser-on-powder based methods. It relies on using semi-solid metals that are solid at rest, but can flow when force is applied, making it possible to move through the nozzle of a printer. Researchers at Lawrence Livermore National Laboratory (LLNL) hope that the process could lead to higher-quality and lighter metal parts.

The team, along with collaborators from Worchester Polytechnic Institute, call the new approach "direct metal writing." Rather than starting with a metal powder as in currently popular 3D-printing techniques like selective laser melting (SLM), a block of metal engineered to be shear thinning is heated until it becomes semi-solid.