TY - CONF A1 - Morys, Michael A1 - Illerhaus, Bernhard A1 - Sturm, Heinz A1 - Schartel, Bernhard T1 - Revealing the inner secrets of intumescent chars by advanced small scale tests combined with µ-CT N2 - Testing of intumescent coatings for Steel is usually done in intermediate scale or even full scale experiments and is hence quite expensive. We developed two complementary small scale tests, simulating fully developed Tire. First is a strongly modified electrical muffle furnace, which is now able to follow the Standard temperature-time curve (according EN 1363-1) for 90 min in a very accurate manner. Düring the experiment backside temperatures are recorded and the growth of the char is observed with a custom made high temperature endoscope. Second is a testing apparatus based on a propane-oxygen-bumer for direct severe flame impingement of coated samples, reaching temperatures far above 1500 °C. Our small scale samples are coated Steel plates of a size of 75 x 75 x 2 mm3. The structure-propertyrelation between additives, thermal properties and morphology of the char were examined using a well determined series of samples consisting of basic composition mixed with different additives. With the burner-testing-apparatus we studied the behavior of a high performance coating, which shows a transformation of the carbonaceous char into a ceramic foam at temperatures as high as 1600 °C. Nondestructive micro-computed tomography was used to characterize the morphology of the char. According to the structure of the foams we used different analytic methods like cell-detection or wallthickness-analysis. Additional scanning electron and optical microscopy were performed. The combination of the CT-data with the measured backside temperatures of the different samples provides us a deep understanding of the interaction between isolating properties and morphology of intumescent chars. T2 - Fire and materials 2015 - 14th International conference and exhibition CY - San Francisco, CA, USA DA - 02.02.2015 PY - 2015 SP - 478 EP - 483 PB - Interscience Communications AN - OPUS4-32710 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -