The Potential of Dynamic Electrochemistry for Post-Processing of 3D-Printed Metal Parts

Abstract

Creativity has no limits with 3D-printing of metals allowing the realisation of new geometries that cannot be provided by any other production method. Nevertheless it is a long way from an innovative idea to a 3D-printing based production process. The 3D-printed metal parts leave the printer with a significant amount of support structures fixed to the part, adhering metal powder and a surface roughness that is much too high for the technical application. While mechanical post treatment methods are mostly work, time and cost intensive they also cannot provide a proper finishing on sterically hindered parts and inner surfaces.Here chemically-electrochemically based methods, such as the Hirtisation® process, enable an integrated production process using the freedom in design of 3D-printing and additionally give an valid option for complete process automatisation that is required for standardisation and qualification of industrial serial production.While classical electro-polishing is failing to adress most of the issues resulting from the printing process, the use of dynamic electrochemistry, in terms of using current or potential pulses to finish the surface of the metal parts, provides a powerful toolbox for this application.This presentation will show the possibilities of dydnamic electrochemistry in terms of applying short current or potential pulses on 3D printed parts and will discuss the use of current pulses on different industrial relevant studies. A key factor for the success of such methods is a knowledge-based electrochemical tailoring of the actual current conditions at the metal surface and a deep understanding and adjustment of the material surface chemistry. Only by such an understanding of the different steps in the production chain and adjustment of these steps to each other, a constant and reproducible quality of the final products can be realised.