Mini sensors for corrosion control

A novel array of sensors is poised to change the costly and resource-intensive process of fighting corrosion in industries such as aerospace, shipping, mining, oil and gas.

The sensors, designed by researchers at CSIRO, indicate where, when and why corrosion occurs. They also convert this information to a real-time management tool which can reduce the costs of maintenance and inspection and improve the safety and integrity of structures.

CSIRO researcher, Dr Tim Muster, says the sensors have been specifically designed to withstand the conditions they need to monitor. The sensors continually monitor the environment in which they have been placed and detect the early onset of corrosion or the environmental conditions conducive to it.

These, and similar purpose-built sensor arrays can monitor not only the appearance and persistence of corrosion, but also its behaviour under different atmospheric conditions including: humidity, temperature, salinity, wind direction and rainfall.

Corrosion control is a costly business. Recent studies estimate that Australia spends $13 billion on monitoring, removing and preventing corrosion.

While some of the new CSIRO sensor arrays have already been sold commercially, most of the research is still regarded as being in the trial stage, with plans to test the sensors under extreme desert conditions in the Middle East and also inside aircraft fuselages.

"This will make maintenance decisions and inspection easier and more accurate," says Dr Muster.

"We are now working on automating this decision-making process so that it guides maintenance schedules and decreases downtime and the frequency of inspections," he says.

Also, as the sensors arm themselves with more and more data, models of atmospheric corrosion for each specific situation or environment can be developed and continuously adjusted.

"This should help industry design materials that are best suited to the environments in which they will be used," says Dr Muster.

As well as exploring new frontiers for the sensors, they also see opportunities to further develop the sensors themselves in terms of more advanced miniaturisation and wireless operation.

One long-term goal is to actually incorporate their sensor technology into paints and coatings, construction materials such as reinforced concrete, and other composites.

The day may come, when there are sensors that can initiate self-repair once corrosion is detected, says Dr Muster.