Holo, Inc. has partnered with high purity powder producer,5N Plus, to present at theASTM International Conference on Additive Manufacturingon Tuesday, November 17 at 9:10am PST. This paper is authored by Sarah Synnestvedt, Katherine Harry and Karthik Bodla from Holo, Inc. along with Etienne Pelletier, Arslane Bouchemit and Amir Nobari from 5N Plus. Here is the abstract for the paper:
Additive Manufacturing (AM) of copper and copper alloys has recently received noticeable attention in many industries. Pure copper is a malleable, ductile, and excellent conductor of both heat and electricity. Also, copper is a natural antimicrobial material that can be applied for various applications related to health and safety. However, copper’s high reflectivity to infrared lasers in Laser- Powder Bed Fusion (L-PBF) systems has created a major challenge to the feasibility of printing high purity copper parts with superior quality. Moreover, the capabilities of L-PBF systems are limited for printing geometries with fine features. Therefore, development of alternative technologies is usually recommended for printing pure copper.
This paper first describes a proprietary atomising technology enabling production of low oxygen- highly spherical copper powders. Key powder characteristics such as particle size, morphology, purity, and oxygen content are discussed. More specifically, the role of an oxide layer at the powder surface is discussed by applying several characterization and analytical techniques.
The paper then describes a Digital Light Processing (DLP)-based AM process for producing high resolution parts from a composite copper-photopolymer feedstock, which after sintering results in pure copper devices with fine features. Using this approach, high density and high purity can be achieved, leading to copper heat transfer devices with designs unconstrained by traditional manufacturing methods. The combination of high resolution DLP printing, unique product design, and high thermal conductivity material results in heat transfer devices with superior thermal performance in comparison to traditionally manufactured devices. Key metrics of density, thermal conductivity, and device performance are discussed.
