Nanopatch for Highly-Stressed Metal Parts

At the Technische Universität Hamburg-Harburg, Professor Marcus Rutner and PhD student Jakob Brunow are developing new long-term protection for metal parts – called a nanopatch. The nanopatch is an ultra-thin coating which is applied to heavily stressed and cyclically strained metal parts (for example bridges). It is designed to delay the formation of cracks and substantially prolong service life. Lower maintenance requirements and longer useful life of metal parts ensure more sustainable deployment of resources. By Ruben Vorwald

The heavy-duty nanopatch has a total thickness of about an eight of the diameter of a human hair and consists of around 160 alternating layers of copper and nickel. In a current study, this nanolaminate coating is applied to the at-risk structural connections of bridges which are exposed to high frequency and heavy traffic like lorries or freight trains. This study focuses on examination of the nanopatch for welding seams. First examinations reveal several and probably simultaneously-acting material mechanisms which increase resistance of the nanolaminate coating to crack formation, and lead to multiple extension of the service life of the welded connections. 

These material mechanisms are being examined in order to understand the interaction of the mechanisms, and to be able to optimise and coordinate the coating to suit the respective degree of cyclic stress. In future, this new technology could substantially extend the service life of steel bridges from the current 80 to 100 years to possibly several hundred years with just very little maintenance required. "The steel industry is a major producer of CO2. With this nanostructured technology, our goal is to reduce the amount of steel used on metal infrastructures and save resources which have a significant impact on the environment“, says Professor Marcus Rutner.
For the tram sector, too, the nanopatch can be a chance to make infrastructure and tram components more durable, more reliable and require less maintenance. At HANNING & KAHL, we are following Professor Rutner’s research with great interest and are curious to find out if the nanopatch can also be applied to our products.