Strength degradation of glass epoxy composites under hygrothermal environment

Abstract

The composite structures are being used in marine applications like boat hulls, propeller blades etc. Apart from these, the composites are used as structural materials exposed to different kinds of degrading environment like temperature and relative humidity. When a fiber-reinforced composite structure is exposed to a hygrothermal environment and mechanical loads, changes in material properties are related to irreversible material strength degradation. The present study deals with the mechanical strength degradation of glass fiber reinforced polymer matrix composites when subjected to hygrothermal environment. The composite cross ply laminates were manufactured by using compression molding process with two types of curing processes cold press and hot press with a bi-directional E-Glass WR 360 as reinforcement, LY556 as resin and HY951 as hardener. The mechanical properties such as Tensile, ILSS, moisture absorption was investigated with different temperatures like 32 °C, 50 °C and 85 °C with time holding of 30 min, 60 min and 90 min in 5% of brine solution. The same mechanical properties are compared with specimens under sealed condition with unsealed condition.