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Additive Manufacturing
Ultrasonic AM enables advancements in heat exchanger technology
This article highlights an additive manufacturing process that provides the same benefits as Laser Powder Bed Fusion ( LPBF ) when applied to 3D print cold plates , but also allows engineers to open up other creative possibilities when designing cold plates for their specific applications :
Ultrasonic Additive Manufacturing .
By Dan King , Additive Manufacturing Project Engineer , Fabrisonic LLC
Push-pull motion from transducers
Downward pressure
Scrubbing motion
Scrubbing motion
Textured ultrasonic sonotrode
Welded foil
One of the articles published by Heat Exchanger World described the benefit of designing and manufacturing cold plates using additive manufacturing ( see box ). The authors helpfully describe what cold plates are , how they are usually manufactured , and the various benefits of designing and producing cold plates using Laser Powder Bed Fusion ( LPBF ) to 3D print cold plates , particularly for applications such as eVTOL aircrafts and other technologies that require small cold plate packaging . Let ’ s now explore another additive manufacturing process that takes designing of cold plates to the next level .
Fabrisonic and ultrasonic additive manufacturing The world of additive manufacturing , also known as 3D printing , has opened the possibility for more complex and efficient heat exchanger devices . When people hear the term 3D printing , they generally think of processes involving
For more information , see the article published in Heat Exchanger World December 2023 ‘ Additive manufactured cold plates : How Conflux Technology is improving thermal performance for Advanced Air Mobility ’ available here : https :// heat-exchangerworld . com / additive-manufactured-cold-plates /
Feedstock foil to be welded
Baseplate
UAM process explained . the melting of a material , whether it be metal or polymer , through hot ends or lasers to gradually print a component layer by layer . However , Fabrisonic has developed a method of printing metals at very low temperatures called ultrasonic additive manufacturing ( UAM ). Fabrisonic is an advanced manufacturing company located just north of Columbus , Ohio in the United States . Here , we have developed and refined a method of bonding metals together without any melting occurring during the printing process . Here ’ s a brief overview of how the process works : metals foils , ranging from < 0.001 ” to 0.015 ” in thickness , are bonded together by a tool that scrubs back and forth between 20,000 and 30,000 times per second . The displacement of the tool side-to-side is on the order of 30-60 microns , a motion which breaks up the oxide layer between the metals . By applying a down force with the tool , combined with this scrubbing motion , a true metallurgical bond is formed between the two foils . The foundation for this process is ultrasonic welding . Fabrisonic has taken traditional ultrasonic welding and more than tripled the power to bond materials like aluminum , copper , steel , and even zirconium , to name a few . The UAM processes uses commercial metal foils rather than metal powders or wires , and does not require high safety processes or controls , as does metal powder 3d printing .
The three main benefits of UAM Because UAM is a very low temperature process , it has benefits over other additive manufacturing technologies . The first of these advantages is bonding dissimilar metals to one another . When melting occurs between two dissimilar metals , brittle intermetallics form between the two materials which can easily crack and form defects . With UAM , since the bonding mechanism is not melting but rather removal of oxides , dissimilar metals can be bonded to one another in the same part . The implication of this benefit is powerful . For example : an aluminum heat exchanger can be printed with copper to improve thermal performance while keeping weight low or printed with unique alloys such as tantalum to protect from radiation .
38 Heat Exchanger World April 2024 www . heat-exchanger-world . com