Just the right challenge
Opened in 2017, the lab was set up to provide innovative technology solutions to support the additive manufacturing industry in powder production and storage, laser powder bed fusion, laser metal deposition, wire arc 3D printing and post treatments.
As 3D printers take no more than a few hours to turn digital data into physical objects while reducing material waste and the need for tools, the technology is likely to see significant growth over the coming years. It is already used in the construction of jet engines and medical applications, for example, increasing the durability of parts and bringing down their costs.
One of the technique’s greatest challenges, however, is to reproduce identical samples. The material properties of 3D printed objects can be influenced by its geometry and the way the printer has been operated, to name but two factors.
The raw materials as well as the actual printing process in the chamber are particularly sensitive to the surrounding atmosphere. Take titanium, for example. Often used in laser powder bed fusion, a technique for printing metals, it slowly reacts with the hydrogen in the air.
“Humid titanium powder behaves like wet flour, it coagulates and loses the ability to close its pores,” Forêt says. “If wet titanium powder is fed into a 3D printer, the printed product will inevitably be of lower quality.” Linde therefore developed a powder cabinet with a controlled atmosphere to keep titanium and other metal powders at optimal conditions.
This is just the right challenge for Forêt and his team. “It is Linde’s core expertise to measure and control the atmosphere. Whether in a printing chamber or elsewhere, we can make sure that the mix of gases is according to specifications.”