由于复合材料在固化过程中产生的残余应力会严重影响材料的使用,并且会带来安全隐患,因此固化残余应力一直都备受关注.首先在研究和测试布拉格光栅温度和应力灵敏度的基础上,将两根光栅分别以平行于碳纤维方向和垂直于碳纤维方向置入铺层的正中间,以此获得复合材料不同方向的残余应力变化情况.监测结果表明,平行方向的光栅在监测固化的过程中受到树脂和纤维的共同作用,且冷却后材料在平行方向显示的残余应力仅有-8.8MPa,而在垂直方向的光栅在监测过程中主要受到树脂的固化影响,收缩应变较大,且冷却后的光栅由于树脂固化不均匀,致使光栅信号分裂为3段.%Because residual stress formed in the curing process can greatly affect the application and will bring security risks of composite material, it is being concerned sincerely all the time. The temperature sensitivity and stress sensitivity of fiber Bragg grating (FBG) were firstly investigated, and then two FBG sensors parallel and vertically to carbon fiber were embedded into same layer in order to in-situ monitor the changes of residual stress. The results show that FBG is affected by the fiber and resin, the residual stress monitored by FBG in parallel direction have only -8.8 MPa. The residual stress monitored by FBG in vertical direction is contracted by resin curing, and the signal is splited into three because of inconsistent resin curing in the grating.
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