What is the context?

Electropolishing is a process where a metal substrate (often steel, aluminum or titanium, but also a wide range of other metals and alloys) is immersed in an acid containing ionic solution (electrolyte) and an anodic electrical current is imposed onto it. This invokes a controlled corrosion process, effectively removing surface roughness and other surface irregularities, such as sharp edges caused by scratches and hair-line surface cracks.
Electropolished surfaces are stress-free and smooth, significantly prolonging the life time of the processed device or part. Often electropolished surfaces also have a mirrored appearance. The process also improves adhesion through the removal of oils and oxides, yielding a clean surface for any subsequent production step.
The product application range is huge, including surgical devices (e.g. stents, needles), nuclear accelerators, sensors, valves, storage tanks etc…

  

What are the issues?

Controlling the current density distribution and electrolyte refreshment (hence effectiveness of the process) over the substrate is a major challenge for electropolishing processes. Poorly controlled current density distributions and insufficient flow refreshment lead to unacceptable roughness values, or might even cause pitting or burning of the product surface.
A dedicated process and cell design is required for each product type. A typical cell design will include a forced flow system with submerged jets or eductors, insulating screens, auxiliary cathodes and/or current thieves.

What value do we bring?

Elsyca has extensive know-how and experience in the design and optimization of electropolishing processes. Elsyca’s advanced engineering solutions will:

• analyze the performance of existing electropolishing cells;
• improve existing electropolishing cells and process parameters;
• design novel electropolishing cells for high-end applications;
• build pilot cells, assembling the complete set-up (electrolyte tank, pump unit, rotameters, sample handling);
• set up and carrying out test program or DoE (Design of Experiment) for pilot cells, examining the electropolished samples.

This will result in:

• enhanced production capacity:
• higher yield (less scrap);
• attaining specifications for a new product;
• reduced lead time for new products.