Advanced Manufacturing

When Powder Metallurgy Builds a ‘Spaceship’

Powder metallurgy uses tiny particles of metal to build unique parts.

See how the 3D-printing company Velo3D used the powder metallurgy process of additive manufacturing to create a microturbine generator roughly the size of a microwave oven.

Enrique Enriquez, president of the Opa Locka, FL-based manufacturer KW Micro Power, turned to t VELO3D’s Sapphire metal powder-bed 3D-printing technology to build a miniature component known as “the spaceship.”

Typically, powder metallurgy process like additive manufacturing require scaffold-like supports to keep a workpiece from drooping or warping during the build process.

Such scaffolds are difficult to make, however, when you have such a complex part like KW’s “spaceship,” which features such small internal channels.

The KW Micro Power component is a titanium disc, roughly 10" in diameter and 4" tall. The interior of the part contains a complex labyrinth that channels exhaust gases far more efficiently than conventional systems.

In a Tech Briefs feature article, learn how Zach Murphree, vice president of technology partnerships at the Campbell, CA-based VELO3D, and his team used powder metallurgy and VELO3D ‘s Sapphire 3D printer to create the spaceship component, the heart of KW Micro Power’s turbine technology, according to Enriquez.

Learn how VELO3D came back with a test piece. The Tech Briefs article offers an up-close look at the VELO3D Sapphire printer.

The VELO3D technology, for example, prints near-horizontal surfaces, without supports. A non-contact re-coater also prevents the build crashes and contamination that may occur when a traditional recoating blade drags across the top of a burgeoning workpiece.

Where most machines use the same laser power, traverse rates, and other build parameters across an entire part layer, Sapphire applies more than 20 geometry-dependent “recipes” to specific sections within each layer. The result is less powder metallurgy stress, greater part accuracy, and faster build times, according to the VELO3D VP.

“We can precisely define how much energy is applied anywhere within the build, which is a large part of the reason why we’re basically support-free,” said Murphree.

The Ti-6Al-4V alloy that Enriquez chose for his microturbine component can be a challenging material to manufacture with. Titanium, in fact, can crack, thanks to all the internal stresses that typically build up with laser sintering processes. In the worst cases, the part essentially tears itself to pieces or rips itself away from the substrate being used in the print process.

The spaceship, in 3D-printing terms, is, in fact, quite massive, said Murphree.

“We knew this going into the project and built in some additional time, but our ability to manage the stress inherent to printing large titanium parts was clearly demonstrated with that successful first print.”

See how VELO3D was able to print the perfect spaceship on the very first try — and make the part 30% lighter. The Tech Briefs article features a variety of images, including cross sections of the part, printed by powder metallurgy.

Read 3D-Printing a Unique Metal Part