Abstract
Composite materials are known to have many advantages and they can be used in the manufacture of a wide variety of products which make them commercially valuable. However, they may come into contact with various conditions that might lead to weathering. Weathering might lead to discoloration, decrease in durability, decline in mechanical properties and decrease in mass in composites. Hence, it is paramount to study the effects of weathering on composites before they are used in service. For this study, wood polyester composite (WPC), jute polyester composite (JPC) and coir polyester composite (CPC) were fabricated and subjected to four weathering tests - water ageing test at room temperature, water immersion test at 100°C, exposure to external environment and exposure to UV rays. It was seen that CPC samples subjected to water ageing at room temperature and immersion at 100°C showed comparatively higher water absorption rate than the WPC and JPC samples as coir fibres in CPC are hollow at the centremost region. JPC and CPC also turned whitish after 24 hours of water ageing. However, exposing the samples to the environment for a period of 144 hours did not show any significant change in the sample. It was also found that the tensile strength of all the composites decreased after being exposed to UV rays in a QUV spray weathering tester. Additionally, the mechanical properties of the composites were also modelled with analytical techniques (Halphin Tsai method) and FEM analysis and the results were found to be analogous.
Aberration-corrected cryoimmersion light microscopy
