Processes

For high precision metal engraving, our process is named “through mask electrochemical dissolution”.

Recent evolution includes nanostructuring of metallic surfaces.

Our Lab also carries electrochemical R&D such as electropolishing or titanium anodization.

Through mask electrochemical dissolution using laser lithography

THROUGH MASK ELECTROCHEMICAL DISSOLUTION

The first step of the process is the coating of the samples with a thin (10µm) polymeric coating. A uniform thickness deposition can be obtained on complex shape objects by electrophoresis. This protective layer is then locally exposed to a focused laser beam. A machine vision imaging setup and motorized stages allow for the precise positioning of the laser irradiation sites. Clean and very reproducible ablation of the film is obtained using a short pulse UV laser. The result of this lithographic process is a precisely microstructured protective coating, with well-defined openings to the underlying metal surface.

The samples are then immersed in an electrolyte. A power supply is connected to provide an electric tension between the processed piece and an inert counter electrode. When optimized voltage profiles and hydrodynamic conditions are applied, the unprotected areas of the workpiece are neatly attacked and a smooth and shiny engraving is achieved. Precise dimensioning of the engraved patterns is obtained by monitoring the electric charge flown through the system. This control is very precise and, unlike chemical etching, is independent of the aging and temperature of the bath.

After accomplishment of the electrochemical dissolution, the polymeric coating is removed with a stripper.

PROCESS CHARACTERISTICS

  • quasi-isotropic engraving (lateral dimensions 10-300 µm)
  • electropolished finish (Ra<25 nm)
  • high precision dimension tolerances (< 1 µm)
  • well established numerical simulation models of etched shapes
  • applicable on 3D and rough surfaces
  • stainless steels, titanium alloys, Ni, NiTi, CoCr,…

Etch profile evolution during dissolution

NANOSTRUCTURING

In collaboration with CSEM, we have developed a joined process for the nanostructuring of metallic surfaces. The process can be applied on 3D surfaces and produces opalescent structural colors.

Opalescent colors on a nanostructured steel rod

TITANIUM ELECTROCHEMISTRY

We are experts in the titanium electrochemical treatments such as electropolishing and colorfull anodisations

Titanium electropolishing

Titanium anodisation

ELECTROCHEMICAL R&D

WE are well equiped for the development and caracterization of electrochemical processes for metallic parts finishing.

Custom electrochemical cell