Laser-induced liquid-phase jet-chemical etching of metals

In this treatment method laser radiation, which is guided from a co-axially expanding liquid jet-stream, locally initiates on a metal surface a thermochemical etching reaction, which leads to selective material removal. Time-resolved measurements of the electrical potential were correlated with the specific processing parameters to identify conditions for stable and enhanced chemical etching reactions. The chemical etching reaction was additionally influenced by an electrical field. Depending on its polarity a significant increase in the etch rate or improvement of the treatment quality was observed. Exemplary, the fabrication of superelastic micro-grippers prepared by cutting of temperature-sensitive shape memory alloys is shown.