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.

中文翻译：

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玻璃纤维增​​强聚酯复合材料在极端低温下的拉伸性能

玻璃纤维增​​强聚合物在高温和低温下都广泛用作结构系统中的承重元件。这项研究提出了在极冷温度下在准静态拉伸载荷下对玻璃纤维增​​强不饱和聚酯的评估。这项工作包括制备聚酯树脂片和E玻璃纤维布增强的聚酯复合材料，以确定在60°C至-80°C的高温至极低温范围内的拉伸性能和破坏模式。结果表明，与未增强的聚酯基体相比，纤维增强的聚酯在所有温度下均具有更高的强度。增强的试样在低于室温（RT）的温度下表现出更均匀的脆性趋势，并且在RT或更高温度下具有合理的延展性。发现未增强材料的拉伸性能在室温以上会降解。该复合材料在最低温度-80°C下具有最高强度。整体聚酯和增强聚酯在低于室温的温度下都具有脆性，尽管增强复合材料显示出轻微的延展性。