As a highly promising lightweight material, carbon fiber reinforced plastics (CFRP) composites have been widely used in aerospace, marine and automotive industries, which could expose to low or high thermal environments with varying material properties. This study investigated the effects of temperature variation ranging from −30 °C to 160 °C on tensile properties of CFRP experimentally and theoretically. The specimens were prepared using thermo-forming technology; and the glass transition temperatures of epoxy resins were measured by dynamic mechanical analysis (DMA). Digital image correlation (DIC) technique was used to capture the variation in strain and damage fields. By means of scanning electron microscopy (SEM), the failure mechanisms, delamination and resin softening, were identified by scrutinizing the images of fracture areas subject to different temperatures. The two-parameter Weibull analysis was conducted to evaluate the theoretical tensile strengths from relatively discrete data. The obtained Weibull parameters are considered useful for the reliability analysis of CFRP structures. It is found that the tensile strength decreases with the increase of temperature in a nonlinear fashion, which can be modeled in terms of a $tanh$ function by correlating with the temperature-dependent experimental data. The study is anticipated to provide fundamental understanding and a predictive tool for mechanical strength of composite structures operating under different thermal conditions.

作为一种非常有前途的轻质材料，碳纤维增强塑料（CFRP）复合材料已广泛用于航空航天，船舶和汽车行业，这些材料可能会暴露于具有不同材料特性的低或高热环境中。这项研究从理论上和实验上研究了温度范围从−30°C到160°C的变化对CFRP拉伸性能的影响。样品采用热成型技术制备。通过动态力学分析（DMA）测量环氧树脂的玻璃化转变温度。数字图像关联（DIC）技术用于捕获应变场和损伤场的变化。通过扫描电子显微镜（SEM）的破坏机理，分层和树脂软化，通过仔细检查受不同温度影响的断裂区域的图像来确定。进行了两参数威布尔分析，以从相对离散的数据中评估理论抗拉强度。认为获得的Weibull参数对于CFRP结构的可靠性分析很有用。发现抗张强度随着温度的升高呈非线性降低，这可以用以下公式来模拟：$Ť\mathrm{一种}ñH$通过与温度相关的实验数据相关联来发挥功能。预期该研究将为在不同热条件下运行的复合结构的机械强度提供基础理解和预测工具。