A Review on Extrusion Additive Manufacturing of Pure Copper

Abstract

Copper, due to its high thermal and electrical conductivity, is used extensively in many industries such as electronics, aerospace, etc. In the literature, researchers have utilized different additive manufacturing (AM) techniques to fabricate parts with pure copper; however, each technique comes with unique pros and cons. Among others, material extrusion (MEX) is a noteworthy AM technique that offers huge potential to modify the system to be able to print copper parts without a size restriction. For that purpose, copper is mixed with a binder system, which is heated in a melt chamber and then extruded out of a nozzle to deposit the material on a bed. The printed part, known as the green part, then goes through the de-binding and sintering processes to remove all the binding materials and densify the metal parts, respectively. The properties of the final sintered part depend on the processing and post-processing parameters. In this work, nine published articles are identified that focus on the 3D printing of pure copper parts using the MEX AM technique. Depending on the type of feedstock and the feeding mechanism, the MEX AM techniques for pure copper can be broadly categorized into three types: pellet-fed screw-based printing, filament-fed printing, and direct-ink write-based printing. The basic principles of these printing methods, corresponding process parameters, and the required materials and feedstock are discussed in this paper. Later, the physical, electrical, and mechanical properties of the final parts printed from these methods are discussed. Finally, some prospects and challenges related to the shrinkage of the printed copper part during post-processing are also outlined.

Dimensional Characterization and Hybrid Manufacturing of Copper Parts Obtained by Atomic Diffusion Additive Manufacturing, and CNC Machining

“…Finally, and in the specific case of ADAM technology, there is still a broad field of study not only with materials like stainless steel, for which there are only a few studies on dimensional or mechanical characterization [ 22 , 34 , 42 , 43 ], but also with other industrially relevant materials such as copper. Additive manufacturing of copper parts is the subject of numerous studies [ 44 , 45 ] due to the combination of the advantages of additive manufacturing and the suitability of the material for both electrical [ 46 , 47 ] and thermal applications [ 48 , 49 ]. Despite this, there are virtually no studies on ADAM with copper material, and even fewer on dimensional analysis, with only a few references related to mechanical characterization and roughness [ 50 ] and electrical discharge machining [ 21 ].…”

Characterization of the Metal Fused Filament Fabrication Process for Manufacturing of Pure Copper Inductors

“…AM enables one to produce optimized geometric features and allows the integration of multiple functions or even sensors directly into parts that are challenging to manufacture or integrate by conventional techniques. While the fused filament fabrication technique (FFF; often referred to as extrusion-based additive manufacturing, MEX) is widely used for polymers or composites [5][6][7][8][9], metal parts are generally manufactured by powder bed fusion processes (e.g., selective laser melting (PBF-LB), electron beam melting (PBF-EB)) or indirect multi-step processes combined with sintering (e.g., binder jetting (BJT)) [10][11][12][13][14][15][16]. The current AM processes for metals produce parts with a relatively high bulk density (greater than 99% for PBF-LB or PBF-EB) but the drawbacks are high machine and operation costs as well as the safety risk of handling the fine metal powders.…”