About the measurement of dynamic mechanical properties of bi-layer systems

Abstract

Abstract The bi-layer system has been well developed for many engineering structural components in the aircraft, automotive, microelectronics and modern space industries in the last few decades. Consequently, a good determination of its dynamic mechanical properties is important for an appropriate design of its industrial application. These studies are usually performed by a three-point bending test using a dynamic mechanical analyzer (DMA). In this work, we show that the three points bending test on a bi-layer system carried out with the test tool provided in a commercial DMA, for example the dynamic mechanical thermal analyzer (DMTA) Rheometric IV, can lead to erroneous results. Measurements on polymer-hard substrate bi-layer systems around the glass transition temperature of the polymer, T g , give larger changes in elastic modulus and loss tangent than they are. This problem is not observed at temperatures lower than T g . The design of new test tool and specimen geometry for the three points bending test is shown together with its application to the measurement of the dynamic elastic properties of a polyvinyl chloride (PVC)–aluminum bi-layer system.