复合材料修补结构腐蚀扩展特性实验研究

为了研究腐蚀环境对复合材料修补结构疲劳特性的影响,开展以某型飞机加速环境谱为基础的预腐蚀试验,并采用递进式的试验方法分别完成对未修补未腐蚀、修补但未腐蚀、又修补又腐蚀的试样疲劳裂纹扩展试验。利用试验数据计算了复合材料修补构型、腐蚀环境对裂纹尖端应力强度因子影响的修正系数,并确定了通过试验验证的修补结构疲劳裂纹扩展修正模型。该模型预测腐蚀环境下修补结构的疲劳寿命与试验值一致。试验数据和预测模型可为海军飞机复合材料修补结构的损伤容限设计提供参考。

Experimental Study of Crack Growth for Pre-Corrosion and Composite Repaired Structure

In order to study the effect of corrosion environment on the fatigue performance of composite repaired structure, pre-corrosion experiment was carried out based on acceleration environment spectrum of a certain type of aircraft. Fatigue crack growth experiment was carried out based on progressive method for the non-repaired and non-corroded specimen, the repaired but non-corroded specimen and both repaired and corroded specimen, respectively. The correction coefficient describing the effect of the composite repair patch and the corrosion environment on the crack tip stress strength factor was calculated based on experimental data; and a modified model of fatigue crack growth in the repaired structure was determined and experimentally validated. Fatigue life of repaired structure in corrosion environment was predicted by the modified model, the prediction is in agreement with the experimental data. Above experimental data and prediction model can provide a reference for damage tolerance design of marine aircraft with composite patch repaired structure.