中文摘要：

为研究Kevlar 49芳纶纤维布增强环氧树脂复合材料在中等应变率和不同温度耦合作用下的力学响应和断裂行为,首先,利用MTS液压伺服高速机在不同初始应变率（25、50、100、200s-1）和温度（-25、0、25、50、100℃）下对芳纶纤维增强复合材料（AFRP）进行单向动态拉伸测试;然后,采用Weibull分析模型量化了拉伸强度在不同应变率和温度下的离散程度。结果表明：在相同温度（25℃）下,随着应变率的增加,弹性模量和拉伸强度均先增大（初始应变率介于25~50s-1范围内）后减小（初始应变率介于50~200s-1范围内）,极限应变则呈现出相反的变化趋势,而韧性随应变率的变化幅度不大;在相同初始应变率（25s-1）下,与在25℃下的情况相比,温度的升高或降低均会造成弹性模量的降低,在温度为100℃时,极限应变显著增加,而拉伸强度和韧性均不会随温度的变化而发生明显改变。对AFRP断裂形态进行的对比分析表明不同试验条件下AFRP的断裂形态基本相同,均呈现出较为平整的断裂面。所得结论可为AFRP在极端载荷和环境作用下的理论研究和应用提供依据。

英文摘要：

In order to investigate the mechanical response and failure behavior of Kevlar 49 aramid fabric reinforced epoxy polymers under the coupling effect of medium strain rates and different temperatures,MTS high rate servohydraulic testing machine was utilized to conduct the unidirectional dynamic tensile tests of aramid fiber reinforced polymers（AFRP）under different initial strain rates（25,50,100,200s-1）and temperatures（-25,0,25,50,100 ℃）firstly.Then,Weibull analysis model was used to quantify the variability degree of tensile strength under different strain rates and temperatures.The results show that under the same temperature（25 ℃）,with the increasing strain rate,elastic modulus and tensile strength both increase firstly（when initial strain rate is in the range of 25-50s-1）and then decrease（when initial strain rate is in the range of 50-200s-1）,while the ultimate strain presents an opposite changing trend,and the changing extent of toughness with strain rate is not obvious.Under the same initial strain rate（25s-1）and comparing with the situation under 25℃,the temperature increasing or decreasing will leads to the decrease of elastic modulus,and the ultimate strain increases significantly when the temperature is 100 ℃,while tensile strength and toughness both change little with the variation of temperature.The comparison and analysis for failure morphologies of AFRP show that the failure patterns of AFRP under different test conditions are almost the same,which present relatively smooth failure surfaces.The conclusions obtained can provide references for the theoretical investigation and application of AFRP under the effects of extreme loading and environment.