yyzmcleod (1534129) writes The technology to 3D print a single part from multiple materials has been around for years, but only for polymer-based additive manufacturing processes. For metals, jobs are typically confined to a single powdered base metal or alloy per object. However, researchers at NASA's Jet Propulsion Laboratory say they have developed a 3D printing technique that allows for print jobs to transition from one metal to another in a single object. From the article: In JPL’s technique, the build material’s composition is gradually transitioned as the print progresses. For example, the powdered build material might contain 97 percent titanium alloy and 3 percent stainless steel at the beginning of the transition. Then, in 1 percent increments between layers, the gradient progresses to 97 percent stainless steel and 3 percent Ti alloy by some defined point in the overall 3D printing process.