Overview: The Potential of silanes for chromate replacement in metal finishing industries

Trialkoxysilanes (or silanes) have emerged as a very promising alternative for chromates in metal finishing industries. Compared to the conventional chromating processes, the major merits of silane-based surface treatments include: eco-compliance, easy-control processing, comparable corrosion protection of metals as well as paint adhesion to a variety of topcoats. In this overview paper, we report the recent status of silane studies including results of corrosion performance tests, the mechanism of corrosion protection of metals by silanes and the themal stabilities of silane films. We also address the new fields that we are beginning to explore such as nano-structured silane films, “self-healing” silane films, and “super-primers”.