In this experimental and statistical study, free vibration behavior of laminated composite beams with functionally graded fiber orientation angles was investigated under clamped-free boundary conditions. The beams were manufactured using E-glass/epoxy. Fiber orientation angles of the beams were analyzed based on Taguchi’s L9 (33) orthogonal array. The effect of fiber orientation angles and beams with optimum levels were assessed using analysis of signal-to-noise ratio. Significant laminates of the beams and their percent contributions on the free vibration responses were obtained using analysis of variance. According to this study, the increase of fiber orientation angle from 0° to 80° causes a decrease in the fundamental frequency behavior of laminated composite beams. The most effective control factors were found to be the first and the second laminates symbolized as L1 with 85.86% contribution, the third and the fourth laminates symbolized as L2 with 12.29% contribution, the fifth and the sixth laminates symbolized as L3 with 1.84% contribution, respectively. This study can be used as a reference for free vibration analysis of cantilever laminated composite beams made of functionally graded fiber orientation angles as experimentally and statistically.

中文翻译：

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具有功能梯度纤维取向角的层压复合梁的实验和统计自由振动分析

在这项实验和统计研究中，研究了在无夹紧边界条件下具有功能梯度纤维取向角的层压复合梁的自由振动行为。梁是使用 E 玻璃/环氧树脂制造的。基于 Taguchi 的 L9 (33) 正交阵列分析光束的纤维取向角。使用信噪比分析评估纤维取向角和具有最佳水平的光束的影响。使用方差分析获得了梁的重要层压板及其对自由振动响应的贡献百分比。根据这项研究，纤维取向角从 0° 增加到 80° 会导致层状复合梁的基频特性降低。发现最有效的控制因素是第一和第二层板标记为 L1，贡献率为 85.86%，第三和第四层板标记为 L2，贡献率为 12.29%，第五和第六层板标记为 L3，贡献率为 1.84% ， 分别。该研究可作为实验和统计上的功能梯度纤维取向角悬臂层合复合梁自由振动分析的参考。