In recent years, several investigators have made efforts to satisfy industrial and transportation demands with respect to high mechanical properties. Moreover, the transparent composites are needed for automotive and aircraft applications. Thus, developing more efficient and advanced transparent composite techniques has recently got more attention but seldom studied in harsh conditions. The main goal of the present study is to investigate the impact of exposing a transparent polyester composite to different temperatures ranging from high to very low (60, room temperature, 0, -30, -60, and -80 C) and 50% humidity. The study of the effect on both fibers and matrix upon exposure to the different conditions and the composite represents an attempt towards climate resistance. In this research, fracture toughness of E-glass fiber reinforced unsaturated polyester composite at high and very low temperatures and humid environments were investigated. The investigation deals with the characterization of fracture strength properties according to the ASTM standards and mechanism of fracture by scanning electron microscopy. The transparent composite was fabricated from the unsaturated polyester matrix and E-glass fibers. Using of E-glass fiber for reinforcing with 15% volume percent for preparation of the transparent composite exhibits fracture toughness at very low temperatures. It was also noted that the technique of giving an excellent transparent polyester composite can be utilized confidently to architect and aircraft structures.

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Despite the excellent performance of stainless steel in diverse application, there are media of exposure may accelerate failure of several stainless steel alloys. The possibility of this failure has to be examined by measuring the effective parameters that may result in corrosion at different rates. The present study has been conducted to examine the effect of exposing specimens of 304 stainless steel to 0.5, 1.0, 1.5 and 2.0 M chloride concentration and 70, 80, and 90 °C. Electrochemical technique of measuring the potentials and currency of the examined system has been used to collect the corrosion data. Microstructure of the specimens is examined using Scanning Electron Microscopy and X- Ray Diffraction. Both of these tests revealed no serious phase change due to exposure even at severe conditions. The potentials gained show significant effect of the operation conditions.

Glass fiber‐reinforced polymers are widely used in structural systems as load‐bearing elements at both high and low temperatures. This investigation presents the evaluation of glass fiber‐reinforced unsaturated polyester under quasi‐static tension loading at extremely cold temperatures. This work includes the preparation of polyester resin sheets and E‐glass fiber cloth reinforced polyester composite to determine the tensile properties and failure modes over a range of high to very cold temperatures over 60°C to −80°C. The results show that fiber reinforced polyester has higher strength at all temperatures compared to the unreinforced polyester matrix. The reinforced specimens exhibit a more uniform brittle trend at temperatures below room temperature (RT) and a reasonable ductility at and above RT. Tensile properties of the unreinforced material were found to degrade above RT. The composite has the highest strength at the lowest temperature of −80°C. Both monolithic and reinforced polyester are brittle in nature at temperatures below RT, though reinforced composites show slight ductility.