Researchers at Bournemouth University have developed and patented a new corrosion sensor that could improve safety and reliability of large structures such as bridges, aircraft, military vehicles and gas pipelines.
The device can detect defects and risks in major infrastructure at a much earlier stage than the methods that are currently used. As well as improving safety, it could reduce the need for time-consuming repairs, which can come at significant cost and inconvenience to industries and the public.
‘Our doctors often encourage us to take health screenings regularly, so they can diagnose conditions at an early stage, which gives us better options for treatment,’ said Zulfiqar Khan professor of design engineering and computing at Bournemouth University. ‘This sensor works on the same principle. If we can spot health risks in vehicles and mechanical structures before corrosion reaches an advanced and dangerous stage, we can avoid costly, lengthy repairs and hopefully prevent structures from being scrapped altogether.’
Currently, corrosion sensors used by industry require cables to be plugged into a computer, which means that maintenance must take place with a worker present at the site. The new device is wireless, so it can be attached to a structure and its readings continuously monitored off-site. And unlike most current devices, which only work on metallic surfaces through which electricity from the sensor can pass, the new sensor can be used on any kind of surface.
‘The aerospace industry, for example, would prefer a sensor that can detect failures beneath non-metallic coatings. Currently, this involves removing a patch of the non-conductive coating to make the conductive surface available – this could be counter-productive as it can initiate corrosion more rapidly,’ Khan explained. ‘Unmonitored failures lead to costly consequences. Scheduled inspections are tedious, time consuming and are mostly limited to visual or surface failures. Our latest sensor technology is a futuristic, much-needed solution. It can work remotely, it works on metallic and non-metallic surfaces, and can detect defects several millimetres below the surface that are not visible to the naked eye.’
The new sensor is the latest development from a series of research projects that began more than a decade ago at the Bovington Tank Museum in Dorset, which holds one of the world’s most significant collections of tanks and other military vehicles. Khan’s team applied their expertise to develop a means to monitor corrosion in the vehicles to help preserve their cultural heritage.
This work ultimately led to the development of a £2.5million conservation centre for the most at-risk tanks. The team also identified maintenance work that could be carried out on some tanks so that they could be driven safely at showgrounds, enabling the public to see them in action.
The new technology has been granted patents in the UK and the USA, and Khan and his team are keen to work with partners so that it can be rolled out across industry, enabling engineering and construction companies to start realising the benefits. As well as its potential uses in operational infrastructure, the device would help companies with large fleets of vehicles or machinery that is be kept in depots and not regularly used or serviced.
‘It is a bit like coming home from work and deciding you want some food that has been at the back of the cupboard, only to find that it is past its use-by date,’ Khan said. ‘Our device can continually monitor mechanical structures to ensure they always remains “in date” and will not have to be thrown out.’