Challenges in 3D Printing of High Conductivity Copper

El-Wardany, Tahany; She, Ying; Jagdale, Vijay; Garofano, Jacquelynn; Liou, J. J.; Schmidt, Wayde R.

doi:10.1115/ipack2017-74306

Cited by 11 publications

(4 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…for different materials such as steels, aluminium, nickel, and titanium alloys [4]. However, the high thermal conductivity of copper challenges laser-based AM techniques to fabricate complex shapes with low porosity [5]. The high thermal conductivity leads to a strong reflection of the thermal energy of the laser or to the transfer of the heat from the melt pool to the previously solidified layer [6][7][8].…”

Section: Introductionmentioning

confidence: 99%

Copper extrusion 3D printing using metal injection moulding feedstock: Analysis of process parameters for green density and surface roughness optimization

Singh

Missiaen²,

Bouvard³

et al. 2021

Additive Manufacturing

View full text Add to dashboard Cite

In the present study, the extrusion-based 3D printing process was explored using metal injection moulding (MIM) copper feedstock to fabricate dense copper parts. The influence of process parameters of 3D printing, namely layer thickness, nozzle speed, extrusion multiplier and extrusion temperature on green density and surface roughness were studied. Based on the central composite design method, a set of experiments was chosen to study the individual and interaction effects of parameters. Analysis of variance was performed to identify the significant factors and statistical models were obtained by regression analysis. The green density was observed to increase with varying the layer thickness from 0.25 to 0.05 mm and nozzle speed from 100 to 20 mm/s. Similarly, surface roughness was improved by decreasing the layer thickness and the nozzle speed and by increasing the extrusion multiplier up to a specific value. The extrusion temperature gave the best results at 200 ℃ for both green density and surface roughness. The significant interactions between the parameters for both green density and surface roughness were also studied. A multi-objective optimization approach was used to maximize the green density and minimize the surface roughness within the range of the parameters. Micro-tomography scans were used to analyze the porosity and voids in samples printed with optimized and non-optimized parameters. Besides, sintering was performed on the optimized printed sample to fabricate a dense copper part and analyze linear shrinkage during sintering. Sintered copper parts with high density and low surface roughness were obtained with the optimized printing process parameters.

show abstract

Section: Introductionmentioning

confidence: 99%

Copper extrusion 3D printing using metal injection moulding feedstock: Analysis of process parameters for green density and surface roughness optimization

Singh

Missiaen²,

Bouvard³

et al. 2021

Additive Manufacturing

View full text Add to dashboard Cite

show abstract

“…Bai and Williams [5] reached 97.3% relative density after sintering with the BJ process. Due to the high thermal conductivity of pure copper and low absorptivity in the range of 25% [11,18] of the copper powder at laser wavelengths of 1000-1100 nm, which are mostly used for LPBF [19], stable processing is not possible for infrared laser powers below 500 W and, therefore, fully dense parts could not be produced [13,20]. So far, only relative densities of 83-88% have been reported for pure copper parts when using a common 200 W infrared laser source [14,21].…”

Section: Introductionmentioning

confidence: 99%

Physical and Geometrical Properties of Additively Manufactured Pure Copper Samples Using a Green Laser Source

et al. 2021

View full text Add to dashboard Cite

So far, copper has been difficult to process via laser powder bed fusion due to low absorption with the frequently used laser systems in the infrared wavelength range. However, green laser systems have emerged recently and offer new opportunities in processing highly reflective materials like pure copper through higher absorptivity. In this study, pure copper powders from two suppliers were tested using the same machine parameter sets to investigate the influence of the powder properties on the material properties such as density, microstructure, and electrical conductivity. Samples of different wall thicknesses were investigated with the eddy-current method to analyze the influence of the sample thickness and surface quality on the measured electrical conductivity. The mechanical properties in three building directions were investigated and the geometrical accuracy of selected geometrical features was analyzed using a benchmark geometry. It could be shown that the generated parts have a relative density of above 99.95% and an electrical conductivity as high as 100% International Annealed Copper Standard (IACS) for both powders could be achieved. Furthermore, the negative influence of a rough surface on the measured eddy-current method was confirmed.

show abstract

“…Although many of the investigations into processing copper with LPBF refer to electrical properties, surprisingly few have reported on the actual conductivity or resistivity achieved. In one of the published works that did report electrical properties, a 300W LPBF machine was used with a copper powder that was first reduced by hydrogen gas to remove oxides, and then coated with a few nanometres of polydimethylsiloxane (PDMS) to inhibit oxidation [30]. The PDMS would then be vaporised in the AM process.…”

Section: Introductionmentioning

confidence: 99%

Electrical resistivity of pure copper processed by medium-powered laser powder bed fusion additive manufacturing for use in electromagnetic applications

Silbernagel

Gargalis

Ashcroft

et al. 2019

Additive Manufacturing

View full text Add to dashboard Cite

Pure copper is an excellent thermal and electrical conductor, however, attempts to process it with additive manufacturing (AM) technologies have seen various levels of success. While electron beam melting (EBM) has successfully processed pure copper to high densities, laser powder bed fusion (LPBF) has had difficulties achieving the same results without the use of very high power lasers. This requirement has hampered the exploration of using LPBF with pure copper as most machines are equipped with lasers that have low to medium laser power densities. In this work, experiments were conducted to process pure copper with a 200W LPBF machine with a small laser spot diameter resulting in an above average laser power density in order to maximise density and achieve low electrical resistivity. The effects of initial build orientation and post heat treatment were also investigated to explore their influence on electrical resistivity. It was found that despite issues with high porosity, heat treated specimens had a lower electrical resistivity than other common AM materials such as the aluminium alloy AlSi10Mg. By conducting these tests, it was found that despite having approximately double the resistivity of commercially pure copper, the resistivity was sufficiently low enough to demonstrate the potential to use AM to process copper suitable for electrical applications. Highlights• Medium powered LPBF machines can process pure Cu to an acceptable level.• Resistivity of as-built Cu increases by 33% depending on initial build orientation.• Resistivity can be reduced by over 50% from as-built conditions via heat treatment.• Electrical resistivity values once heat treated are lower than AlSi10Mg values.

show abstract

Challenges in 3D Printing of High Conductivity Copper

Cited by 11 publications

References 0 publications

Copper extrusion 3D printing using metal injection moulding feedstock: Analysis of process parameters for green density and surface roughness optimization

Copper extrusion 3D printing using metal injection moulding feedstock: Analysis of process parameters for green density and surface roughness optimization

Physical and Geometrical Properties of Additively Manufactured Pure Copper Samples Using a Green Laser Source

Electrical resistivity of pure copper processed by medium-powered laser powder bed fusion additive manufacturing for use in electromagnetic applications

Contact Info

Product

Resources

About