Comparisson of Tg values for a graphite epoxy composite by differential scanning calorimetry (DSC), thermomechanical analysis (TMA), and dynamic mechanical analysis (DMA)

Abstract

The effect of sample environment and test method on the apparent T g of graphite-epoxy composites was investigated by thermomechanical analysis (TMA), differential scanning calorimetry (DSC), and dynamic mechanical analysis (DMA). Samples were prepared under controlled conditions and stored in a controlled environment before testing. Specimens were examined on the TMA in penetration, flexure, and thermal expansion, as well by DSC and DMA in both flexure and torsion beam. The measured T g was found to be affected by moisture content, the instrument used, and the test method selected. Recommendations for the comparison of T g values are discussed