Dr.-Ing. Özlem Özcan builds an electrochemical laboratory universe at BAM to develop sensors that can differentiate between the progress of uniform and localised corrosion.

Dr.-Ing. Özlem Özcan builds an electrochemical laboratory universe at BAM to develop sensors that can differentiate between the progress of uniform and localised corrosion.

Source: BAM, photo: Michael Danner

Özlem Özcan is heading a start-up project: it involves the measurement of pitting on metals caused by bacteria.

Help is particularly needed from neighbouring co-workers in microbiology. The chemist Özlem Özcan is breeding bacteria with their help. She needs the microorganisms for her experiments, but cannot culture them herself. Therefore, she makes an interdisciplinary excursion next door. Later Özlem Özcan puts the bacteria on a metal sample where she wants to measure the biofilm formed by the bacteria on the surface. This is why the scientist needs her laboratories. Özlem Özcan builds an electrochemical laboratory universe at BAM so week after week new technologies are added, she also sets up test sites and laboratories, drafts project proposals and submits them to funding agencies. A lab engineer and three Ph.D. students are already there and soon there will be seven of them. One can feel a spirit of optimism here.

In an electrochemical measurement cell, bacteria and the metal sample are hermetically sealed. The bacteria’s behaviour is measured using electrochemical and spectroscopic methods over a number of hours or even days. Namely, a localised corrosion can often take place under a biofilm, which is dangerous. "Studies have shown that it is responsible for more than 75 percent of sudden material failures," says Özlem Özcan. The microbial triggers thrive in oil and wastewater treatment plant pipes, the food manufacture industry and in the saline environment of offshore engineering parts or in ballast tanks. "The challenge is to develop sensors that can differentiate between the progress of uniform or localised corrosion," says the chemist. The goal is to establish an early warning system. But first, she looks at the basics and, simply put, at the corrosion basics of deterioration.

Even "stainless" steels, i.e. high-alloy materials, are susceptible to pitting corrosion. These composite materials are in demand in all sectors of industry, new ones are being developed all the time. They must be lighter, stronger and more durable. "Methods that simulate coupled stress scenarios and can clarify damage mechanisms are important," says Özlem Özcan. "We will use this knowledge to contribute to material safety." She herself graduated as a chemical engineer in Turkey and earned her Ph.D. in materials science in Germany. She investigated nanostructured thin films and lightweight materials in the car industry and joined BAM in April 2015. She will continue to deal with the issue of mobility, new project applications are ready and waiting in this field. Current problems include how hybrid components can best be glued or processed to enable them to simultaneously withstand mechanical and corrosive stress.