Glass sensors measure weathering effects

Sep 26, 2004

The corrosiveness of a specific atmosphere can be established in a few weeks by thin slices of special glass. The sensors are capable of monitoring the outdoor environment as well as indoors, for instance in sensitive production processes such as chip fabrication.


Where does a Landrover develop rust faster: in the dusty Sahara or parked in front of an English stately home? The answer’s obvious: In rainy Britain of course. But the rate at which corrosion sets in is not only dependent on precipitation. It also involves other factors like humidity and temperature, and the concentration of air pollutants such as nitrogen oxides and sulfur compounds. Traditionally, each of these parameters is measured separately, making it difficult to predict their corrosive effect, because this depends on the interaction of all variable factors. Scientists at the Fraunhofer Institute for Silicate Research ISC have developed a glass sensor that allows the complex effect to be calculated even before the vehicle starts to rust. The manufacturing process for the glass sensor has been validated according to German VDI guideline 3955/2.

The glass plates have a polished surface that is highly sensitive to corrosion. “This allows us to detect changes long before the exposed materials or objects show any signs of damage,” explains Hannelore Römich, head of the department for conservation of historical artifacts. The researchers place the glass sensors in small holders at the site in question. A few weeks later, they collect the plates and analyze them using infrared spectroscopy. This allows them to quantify any changes in the composition of the glass. From these data, they can extrapolate the probable damage to other inorganic materials such as stone or metal, and identify the specific pollutants responsible for the corrosion. By examining the plates under a microscope, the scientists can also tell whether microorganisms play a role in the weathering process.

“The sensor has already been employed to good effect on historic monuments, stained-glass windows and in museums,” reports Hannelore Römich. “In each case, the thin glass plates were extremely useful in helping to improve the conditions needed to preserve the works of art.” The researchers recently took measurements at the DaimlerChrysler site in Sindelfingen near Stuttgart, to determine whether the air in the vicinity of the carmaker’s world-largest production plant is too corrosive. A false assumption, as the sensors proved. The inventors of this simple test also see other potential applications, for instance monitoring the air in chip-fabrication facilities, where a corrosive atmosphere would damage the delicate components. To make this possible, the researchers have improved the sensitivity of the sensor. Special coatings make it three to ten times more sensitive and hence faster.

Source: Fraunhofer-Institut für Silicatforschung

Explore further: Samsung delays Tizen smartphone sales launch

add to favorites email to friend print save as pdf

Related Stories

A global view of oceanic phytoplankton

Jul 18, 2014

University of Maine oceanographer Ivona Cetinic is participating in a NASA project to advance space-based capabilities for monitoring microscopic plants that form the base of the marine food chain.

Getting a charge out of water droplets

Jul 11, 2014

Last year, MIT researchers discovered that when water droplets spontaneously jump away from superhydrophobic surfaces during condensation, they can gain electric charge in the process. Now, the same team has demonstrated that ...

Samsung looks on as profits migrate to online ecosystems

Jul 09, 2014

There used to be a time when the launch of a Galaxy handset, a Macbook, or a fancy game console could set investor hearts on fire and firms on a path to untold riches. These days, new devices no longer have ...

Recommended for you

Google searches hold key to future market crashes

59 minutes ago

A team of researchers from Warwick Business School and Boston University have developed a method to automatically identify topics that people search for on Google before subsequent stock market falls.

Lenovo's smart glasses prototype has battery at neck

3 hours ago

China's PC giant Lenovo last week offered a peek at its Google Glass-competing smart glass prototype, further details of which are to be announced in October. Lenovo's glasses prototype is not an extreme ...

Amazon launches 3D printing store

5 hours ago

Amazon announced Monday the launch of an online store for 3D printed items to allow consumers to customize and personalize items like earrings, pendants, dolls and other objects.

User comments : 0