SurTec 685 is a new thick layer passivation for alkaline zinc and zinc/iron (300-400 nm) with outstanding properties: unlike all other known high performance passivations, its corrosion resistance is not reduced after heat treatment (e.g. 24 h x 120 °C or 8 h x 210 °C) but even improving drastically.
Nearly no black spots are observed during corrosion test. The bath has milder conditions than Chromiting, thus less consuming the zinc or zinc/iron layer. It is treatable with SurTec 680 IAT in order to extend service life. In addition, it is cobalt-free, so Co itself as well as Cr(VI) traces are not an issue anymore.
SurTec 685 is a powerful new passivation for alkaline zinc and zinc iron. A patent application has been filed.back to overview