碳纤维织物布层压复合材料湿热环境疲劳后剩余压缩强度

为了研究湿热环境对碳纤维织物布层压复合材料疲劳性能的影响,开展了碳纤维织物布含中心孔层压板疲劳试验和剩余压缩强度试验,并为湿热环境拉-压疲劳试验自行设计了湿热环境试验箱。参照ASTM标准设计加工了疲劳试验夹具和压缩试验夹具,分别在标准环境条件(温度(23±2)℃、相对湿度(50±5)%RH),湿热环境条件(温度(70±2)℃、相对湿度(85±5)%RH)下对试件进行拉-压疲劳试验,之后分别进行了剩余压缩强度试验。以标准环境疲劳试验件的剩余压缩强度为基准值,对比湿热环境疲劳试验件的破坏载荷对应的极限压缩强度,计算其与基准值的差值。通过试验结果对比,得到湿热环境下试验件疲劳后剩余压缩强度下降了14%,该湿热环境对载荷谱下的碳纤维织物布层压复合材料试验件疲劳后剩余压缩强度影响较小。

Residual compressive strength after fatigue of carbon fiber fabric composite laminates in hydrothermal environment

In order to study the effect of hydrothermal environment on the fatigue properties of carbon fiber fabric composite laminates, the tests of carbon fiber fabric on fatigue and residual compressive strength with the center-hole laminates were carried out. For the tests on tension-compression fatigue in hydrothermal environment, a chamber used for hydrothermal environment was designed. In accordance with ASTM standard, the fatigue test fixture and compression test fixture were designed and produced. Then the tension-compression fatigue tests of specimens were carried out in conditions of standard environment conditon (temperature of (23±2)℃, relative humidity of (50±5)% RH) and hydrothermal environment condition (temperature of (70±2)℃, relative humidity of (85±5)% RH). After that, the residual compressive strength tests were carried out, respectively. The residual compressive strength after fatigue in condition of standard environment was set as a reference value, compared with the ultimate compression strength corresponding to the failure load in condition of hydrothermal environment, calculating the difference between them. According to the comparison of test result, it shows that the residual compressive strength of specimens after fatigue in condition of hydrothermal environment decreases by 14%, so the hydrothermal environment has little effect on the residual compressive strength of carbon fiber fabric composite laminate specimens after fatigue under load spectrum.