3DM Surface Finishing has developed a new polishing technology for metal 3D printed parts, with assistance from AMTIL’s Additive Manufacturing Hub (AM Hub).
Based in Port Melbourne, 3DM has been at the forefront of metal surface finishing technology for more than 25 years, with international sales based on patented technologies. Its new technology, based on electro polishing, overcomes historical limitations to achieve surface finishes of less than 4 Ra surface roughness in under five minutes – delivering outcomes that previously took 30 to 60 minutes. This new technology enables surface smoothing to be shape-sensitive, predictable and controllable like never before.
Metal 3D printing has enabled the design freedom and mechanical optimisation of parts never seen before. When using laser powder bed fusion (LPBF) technology, the surface finish is an intrinsic part of the design requirement; this is particularly the case in medical applications, where it can help to prevent bacteria growth, enable bone osseointegration, provide corrosion resistance, optimal fluidics or mechanical strength.
Surface finishing technologies to date have largely been ‘adapted’ from traditional machining industries, and not readily transferrable to the complex geometries and selective surface requirements of metal 3D printing. Most frustratingly, parts spend up to four times longer in post-processing than the time it took to print them.
3DM needed to overcome the inherent challenges of electro-polishing in the context of metal 3D printing, while providing surface finish control and significant time savings.
3DM needed to combine its extensive experience of electro polishing with the most recent knowledge in LPBF, so the expertise available at Amiga Engineering and CSIRO’s Lab 22 facility was co-ordinated through the Additive Manufacturing Hub.
The project required a combination of expertise covering electro-polishing, materials science and LPBF part printing to understand the competing constraints, yet still remain focused on the goal of time savings and surface finish control. New metal and alloy combinations available to LPBF but not common in traditional machining required new knowledge to be built and applied to the advanced ‘electro-ablation’ technique.
3DM is now optimising its advanced electro-ablation technique for common metal 3D printing materials and surface contours.
How the Additive Manufacturing Hub helped
Lab 22 provided the valuable materials science insights relevant to metal 3D printing using the LPBF process. Amiga Engineering printed parts using the specified materials for 3DM to undertake iterative development and optimisation.
The AM Hub’s Build it Better voucher program enabled deep knowledge domains to collaborate and share insights, ultimately ensuring the rapid acceleration of product development for commercial benefit. The metal 3D printing sector is growing rapidly and requires a diverse knowledge base to translate great science into commercial impacts.
The project enabled the cross-fertilisation of knowledge not readily transferred in industry. The primary goal of rapidly reducing the surface finishing time was achieved, in some cases up to 90%. This is of primary interest to industry, as it immediately translates to productivity and competitiveness. An additional benefit of the project was the unforeseen importance of printing strategies, specifically the influence it has on the ‘as printed’ surface finish and part density, as both these factors contribute to the polishing outcome. 3DM Surface Finishing have now included these insights into the product, optimising the benefits of electro-ablation of 3D metal parts for both manual and automated processes.
The AM Hub is an initiative delivered by AMTIL in partnership with the Victorian State Government to promote the adoption of additive manufacturing technology. For more information, please contact John Croft, AM Hub Manager, on 03 9800 3666 or email