When designing equipment for advanced research facilities, there are extremely high demands on both quality and function. Recently, a demonstration at the Danish Technological Institute showed, that the two things can be combined using 3D printing.
The Danish Technological Institute's subsidiary, Danfysik, had a customer with some requirements for a special product design - a so-called vacuum chamber - which at the same time had to be able to be cooled effectively. Therefore, Danfysik chose to contact the 3D printing specialists at the Danish Technological Institute, also known as DTI.
Together, Danfysik and DTI designed a chamber - also known as a 'Drift tube linac vacuum chamber' - which met the very specific requirements, and which was also optimized for 3D printing. Subsequently, a demo part was printed in stainless steel (316L).
Completely sealed chamber with built-in cooling channels
The vacuum chamber is made with specially designed cooling channels built into the walls, so that you achieve a much more efficient cooling. This possibility of making internal cooling channels is one of the great advantages of the 3D printing technology, which is also known as additive manufacturing.
The 3D-printed chamber has of course been thoroughly tested to ensure that it meets the strict requirements - and at Danfysik, it has not been possible to measure leaks with the measuring equipment available. More specifically, the chamber has been tested to two sizes better than typical requirements for such vacuum chambers, and no leaks have been found.
Metal 3D printing holds some exciting possibilities for new product designs, and after we have verified that 3D printed parts are compatible with high vacuum, it's definitely a technology that we will consider in the future
- Jesper Kristensen, Danfysik
The test equipment (and we apologize if it gets a bit technical) can measure leak rates down to 1*10-12 mbar*l/s. A typical specification for this type of chamber is a leak rate better than 1*10-10 mbar *l/s - so the 3D-printed chamber is well within the limits. In addition, Danfysik has calculated the outgassing rate. It indicates how many foreign atoms are found on the surface of the material, and this also looks fine in relation to the requirements.