EFFECT OF HUMIDITY ON THE DIMENSIIONAL STABILITY OF POLYMER COMPOSITE MATERIALS

Abstract

This research analyzes the hygrothermal properties of carbon fiber epoxy composites by investigating the effects of temperature (ranging from 10 C° to 50 C°) and high relative humidity (90%) on the dimensional stability over different durations. A full experimental procedure was done on thirty specimens placed in a climate chamber at the specified temperatures and 90% relative humidity for different time intervals up to 432 hours. A baseline of 14.76 mm Average width and 3.19 mm Average thickness was established.

Dimensional changes included width increase at 10 C° (1.63% to 15.00 mm), 20 C° (1.35 % to 14.96 mm), 40 C° (2.03% to 15.06 mm) and 50 C°(0.27% to 14.80 mm),   however, thickness slightly change (0.31%)  at 10 C° , 20 C, 50 C° and (0.94%) at 40 C°   temperatures. While at 30 C°, width increase (0.068% to 14.77 mm) and the thickness remains the same .The temperature and humidity conditions had clear and profound effects on the mechanical properties of composite materials, thus hygrothermal testing should be used to enhance the durability of composites.