Scientists at the Fraunhofer Institute have reportedly expanded its high-speed testing machine with a cooling device that enables plastics to be examined at lower temperatures without a thermal chamber.

The device is validated down to minus 40°C, using compressed air cooled by liquid nitrogen, with the sample standing in the air flow, Fraunhofer said. The cooling device developed at Fraunhofer LBF consists of a controller and switching element, a cold reservoir, a nitrogen tank and a supply line to the sample. A thermal camera monitors the temperature over a large area, and the team starts the measurement as soon as the desired temperature is reached. The advantage of mixing compressed air and nitrogen is that the compressed air is dry and only a few ice crystals form on the sample surface, and the gas mixture from the cold reservoir ensures a more constant temperature of the air flow than when nitrogen is applied directly, according to the scientists.

This story uses material from Fraunhofer, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier.