Solukon
With the launch of its SFM-AT350-E depowdering system, Solukon has extended the vibration options within automated depowdering with ultrasonic excitation.
Going beyond the combination of automated rotation and targeted vibration, Solukon's SFM-AT350-E solution provides enhanced depowdering in long and narrow channels.
One company to have benefited from the new system is justairtech, a manufacturer of highly efficient cooling systems that use air as a refrigerant, primarily targeting data centers and industrial cooling needs. Having additively manufactured a Fractal Heat Exchanger, which is designed to be 4-5 times higher efficiency than conventional systems, justairtech turned to the SFM-AT350-E system to remove excess powder from the part's tight channels.
How the process unfolded
Solukon
Before the ultrasonic depowdering process in the SFM-AT350-E, a pre-cleaning was conducted. There was a period of time between the first and second cleaning during which the component was exposed to normal room air. It can therefore be assumed that the powder remaining inside the part reacted with moisture from the surrounding air, which would further complicate the depowdering process.
The depowdering process was carried out on the SFM-AT350-E with permanent ultrasonic excitation and without an option for a pneumatic vibrator or high frequent knocker. During the depowdering, a high impact blasting gun was also used to loosen the powder. During depowdering in automatic mode (swiveling angle 60°-220°, rotating and swiveling speed 10°/s with waiting times of 5 seconds in each position), a strong powder flow was detected. All in all, the ultrasonic depowdering process of this Fractal Heat Exchanger on the Solukon SFM-AT350-E took 337 minutes. Despite pre-cleaning, more than 1.9 kg of stainless steel powder that had attached could be removed. The Heat Exchanger is now completely depowdered.
This use case clearly demonstrates that ultrasonic excitation can make a significant difference when dealing with narrow, long channels. Considerably more powder was removed compared to conventional pre-cleaning using vibration and knocking. Ultrasonic cleaning with the SFM-AT350-E is another powerful tool in Solukon’s comprehensive industrial depowdering toolbox. However, the choice of excitation method still heavily depends on the geometry of the part.
Solukon
“The powder removal test impressively confirmed that even powder that gets stuck in component areas that are extremely difficult to access - in our case over 1.9 kg - can be removed automatically. The comparison with the target weight of the heat exchanger shows that the test with Solukon was extremely successful and that the component is now free of powder. This not only provides us with the necessary process reliability, but also strengthens our confidence in the industrial series application of additively manufactured components.” – Philipp Komurka, Head of Product Development & Technology Additive Components & Testing at justairtech.
Part dimensions (incl. build plate): 350 x 350 x 350 mm
Printer with which the part was manufactured: EOS M 400-4
Material: EOS Stainless Steel 316L
Application: Fractal Heat Exchanger
Structure / surface: Complex internal geometry with many horizontally running, long and narrow channels; Channel opennings of various geometrical shapes; Spread over the entire base area, approximately halfway up: an area (100 - 150 mm high) in which there is a vertical grid with extremely small gaps (“channels” of 0.5 x 0.5 mm).
Smallest diameter of internal feature: 0.5 x 0.5 mm
Duration of automatic depowdering: 337 min
Depowdering system: Solukon SFM-AT350-E with ultrasonic excitation
Mode used: Automatic mode + manual mode
