In order to study buckling fatigue behavior and failure modes of 2A97 Al-Li alloy stiffened panels under shear loading, 1.2 mm and 1.5 mm thick 2A97 Al-Li alloy stiffened panels were designed and manufactured. The static and fatigue tests were performed under shear loading. The results indicate that the shear failure modes of stiffened panels are global buckling wave, skin cracks and rivets falling off. The effect of skin thickness on the buckling load is greater than that on the ultimate load. The fatigue failure processes of stiffened panels include gradual failure and catastrophic failure. The fatigue failure modes are complex and rivet falling off is most dangerous. Panels with cracks or broken rivets still has residual life. Once the skin tears, the panel will immediately fail. The total fatigue life and initial fatigue life of 1.5 mm stiffened panel are 28.87% and 59.88% higher than those of 1.2 mm stiffened panel respectively, while the residual life is 87.68% lower. The finite element models were established to simulate the buckling and post-buckling process of the stiffened panels, and the local stress spectrum of the fatigue dangerous point was obtained. Goodman's theory and nominal stress method was combined to predict the fatigue life and to explain the experimental findings.

为研究2A97铝锂合金加筋板在剪切载荷作用下的屈曲疲劳行为和失效模式，设计制造了1.2mm和1.5mm厚的2A97铝锂合金加筋板。静态和疲劳试验在剪切载荷下进行。结果表明，加筋板的剪切破坏模式为整体屈曲波、表皮裂纹和铆钉脱落。蒙皮厚度对屈曲载荷的影响大于对极限载荷的影响。加筋板的疲劳失效过程包括逐渐失效和灾难性失效。疲劳失效模式复杂，铆钉脱落最为危险。有裂纹或铆钉断裂的面板仍有剩余寿命。一旦皮肤撕裂，面板将立即失效。总疲劳寿命和初始疲劳寿命为1。5mm加筋板比1.2mm加筋板分别提高28.87%和59.88%，剩余寿命降低87.68%。建立有限元模型，模拟加筋板的屈曲和后屈曲过程，得到疲劳危险点局部应力谱。Goodman 的理论和名义应力法相结合来预测疲劳寿命并解释实验结果。