TEMPERATURE CHANGES IN POLYMER COMPOSITES DURING TENSILE LOADING

摘要

Temperature changes in polymeric composite laminates subjected to uniaxial monotonic tensile loading were studied. The laminates were transverse and longitudinal unidirectional glass fibre-epoxy and carbon fibre-epoxy laminates, and hybrid crossply laminates with longitudinal glass fibre-epoxy and transverse carbon fibre-epoxy layers. The temperature decreased linearly with increased tensile stress in the elastic region, except for longitudinal carbon fibre specimens (where the fibres have a small but negative coefficient of thermal expansion), which exhibited a small temperature increase. The occurrence of non-linear stress-strain behaviour in transverse carbon fibre specimens altered the rate of temperature change. When cracks appeared in laminates, the temperature immediately started to rise. The temperature changes in crossply laminates were interpreted from measurements on unidirectional specimens and knowledge of the damage mechanisms. [References: 16]