A robot arm takes over the fully automatic handling of the test melts in the glass screening unit – here, the pouring of the melt into the sample form.
Model by model, electronics in a car are being moved closer to the engine block. This is why the materials used for the electronics must resist increasing heat – so the glass solder being used as glue must be continually optimized. For the first time ever, a robot takes on the task of developing new types of glass and examining their characteristics. Researchers will introduce this robot soon.
WURZBURG, GERMANY: For a laymen glass looks transparent, but it consists of 50 to 60 different elements. Experts are constantly being asked to create glass with certain characteristics out of these elements, since new applications require new materials. For a car, electronic components in the engine compartment are being brought ever closer to the engine and so must increasingly be resistant to heat and corrosive gasses. This also applies to the glue, a glass solder that is used in fuel cells. In addition, over 100,000 hours, glass must withstand thermal heat of 900 degrees celsius without being damaged.
In order to develop glass with new characteristics experts select about ten compounds from potential elements, mix them and then heat the powder. They heat it in a furnace and then pour it into a mould and let it cool slowly, in a controlled fashion. During that process small samples from the viscous glass are taken to test it. To produce glass samples by hand and to test them requires a lot of time - one employee needs approximately two weeks to process 16 samples.
Researchers of the Fraunhofer Institute for Silicate Research ISC in Wurzburg have developed a unit that carries out all these steps automatically.
“It needs only 24 hours to process 16 samples. For this reason we are able to develop glass elements more cost-effectively than previously, by up to 50 per cent,” said Dr Martin Kilo, Manager of the Expert group for glass and high-temperature materials at ISC.
The core piece of the unit is a robot: it puts a mixing cup on a scale and moves it under 14 storage vessels, from which a certain amount of powder is filled into the cup. Then the robot mixes the individual ingredients by closing the cup and shaking it. The robot arm then fills a crucible with a certain amount of the mixed powder and puts the crucible into one of the five furnaces available in total. The furnace heats the fully filled crucible to a higher temperature, causing gas bubbles in the glass to rise to the surface. Once the glass is viscous, the robot arm removes the crucible, pours the glass into a new mould and places it in a stress-relieving furnace. The glass cools slowly and in a controlled manner, from 600 to 800 degrees celsius down to room temperature.
An additional central element of the unit is the analysis unit. The unit also determines and records the ability of the glass to conduct heat.
(C) 2011 Fraunhofer Institute News