December
2003
Photoelectropolishing of Stainless Steel
Herein we present a study on photoelectropolishing
of stainless steel sheets. The advantage
of this manufacturing process is that
smooth surface finish is achieved where removal takes place. The areas being protected
against removal by photoresist are not removed.
Therefore. structuring takes place.
This makes the process one of the electrostructuring
processes,II I Electrochemical
removal processes 8rc characterised by the
combination of electropolishing and structuring
by the usc ofany kind of resist that
prevents metal from electrochemical removal.
Different from photoetching, spray etchin”
and PCM (photochemical machining), 12-10 the
removal takes place without build-up of local
cells.[III The electrochemical removal process
occurs when a current now is applied to the
system by usc of an outer power supply. The
metal componenls of the alloy are oxidised al
the unprotected areas of the anodic workpiece.
In contrast to PCM f12J it is quite easy to
achieve shiny and smooth surfaces between
the embossed structures.[l3-14J By using differelll
pholomasks, different structures can be
produced in a flexible and casy way. Using
lithographieal teclmiques, the etching stencil is
made with the help of the photomask[I-4) After
exposure, development and rinsing, the workpiece,
now partly coated with the etching stenci~
is placed in a special electrolytic solution.
Switching on the current starts the anodic removal
process. The metal is dissolved at the
uncovered areas of the sheet surface.
Dr.-Ing. M. Buhlert, University of Bremen, Dr. K. Meier, HTP HiTech Photopolymere AG, and Prof. Dr. P.J. Plath, MIR-Chem GmbH
