内埋光纤光栅碳纤维增强复合材料层压板力学性能及拉伸应变监测

STUDY FOR MECHNICAL PROPERTIES OF THE COMPOSITE LAMINATES EMBEDDED WITH THE OPTICAL FIBERS

将不同数量的光纤光栅埋植于复合材料层压板层间部位,研究了光纤光栅的埋植数量对层压板拉伸和压缩性能的影响及光纤光栅埋入对层压板层间结构的影响。此外,利用埋植在层压板内部的光纤光栅监测了层压板在拉伸过程中的应变变化,并与应变片监测结果进行了对比。试验结果表明,当在复合材料层压板中沿纤维方向埋入光纤光栅时,复合材料0°拉伸强度和模量略有降低。而当光纤光栅垂直于纤维方向埋入复合材料内部时,复合材料的90°拉伸强度和模量略有提高。对于压缩性能而言,由于光纤光栅在压缩过程中发生脆断,在复合材料内部产生损伤源,导致复合材料压缩强度有所降低,但当光纤光栅埋植数量较小时,对压缩模量的影响较小。层间形貌的显微观察结果表明,光纤光栅沿纤维方向埋入复合材料内部,在光纤光栅周围未形成树脂富集区,反之则将出现明显的富树脂区。

In this paper,Fiber Bragg Grating（FBG） was embedded into the composite laminates and the effect of the number of the FBG on the tensile and compression properties of the composite laminates were studied,also the micrograph of interlayer.Furthermore,the embedded FBGs were used as the sensors to monitor the tensile strains and compared with the strain gage.It was shown that,when FBGs were embedded into the laminates along the fiber direction,the 0° tensile strength and modulus of the composites were slightly declined.Whereas,when FBGs were embedded into the laminates perpendicular to the fiber direction,the 90° tensile strength and modulus of the composites were slightly increased.For the compression performance,because of the broken-down strength of FBG was lower which will induced the stress concentration inside the composite laminates,and therefore lead to the decrease of the compression properties.It was shown from the micrographs of interlayer that when FBGs were embedded perpendicular to the fiber direction,resin-rich area will be clearly observed around the FBGs.