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采用单向硼纤维/环氧复合材料补片真空袋压工艺单面修复不同厚度含中心裂纹铝合金板,测试了修复试件的热学及准静态力学性能,并采用三维有限元模型分析了修复试件的残余热应变和应力强度因子。结果表明:修复试件的弯曲挠度随铝合金板厚度增大而减小;修复试件铝合金板下表面裂纹尖端附近的残余热应变随铝合金板厚度增大而增大,补片上表面的残余热应变则随铝合金板厚度增大而减小,这与有限元分析结果吻合较好。含中心裂纹铝合金板的应力强度因子随铝合金板厚度增大而减小,而单面修复试件的应力强度因子随铝合金板厚度增大而增大。采用相同长度和宽度的单向硼纤维/环氧复合材料补片单面修复后,铝合金板厚度为1.76 mm修复试件的承载能力保留率为93.85%,而厚度为10.20 mm修复试件的只有84.01%;修复试件的刚度得到了完全恢复,等效刚度均大于完好试件的刚度。
The uniaxial boron fiber / epoxy composite vacuum bagging process was used to repair single-sided aluminum alloy plates with different thickness and central crack. The thermal and quasi-static mechanical properties of the repaired samples were tested. The three-dimensional finite element model was used to analyze the repaired Residual thermal strain and stress intensity factor of the specimen. The results show that the bending deflection of the repaired specimen decreases with the thickness of the aluminum alloy sheet. The residual thermal strain near the crack tip of the lower surface of the aluminum alloy specimen increases with the thickness of the aluminum alloy sheet. The residual thermal strain decreases with the thickness of the aluminum alloy plate, which is in good agreement with the finite element analysis. The stress intensity factor of the center cracked aluminum alloy plate decreases with the increase of the thickness of the aluminum alloy plate, while the stress intensity factor of the single-side repair specimen increases with the increase of the thickness of the aluminum alloy plate. The uniaxial boron fiber / epoxy composite patch with the same length and width was repaired with one side, the thickness of the aluminum alloy patch was 1.76 mm, the retention rate of the test piece was 93.85% and the thickness was 10.20 mm Only 84.01%. The stiffness of the repaired specimen has been completely restored, and the equivalent stiffness is greater than the stiffness of the intact specimen.