Multipoint cure monitoring of temperature and strain of carbon fibre-reinforced plastic shafts using fibre Bragg grating sensors
Multipoint cure monitoring of temperature and strain of carbon fibre-reinforced plastic shafts using fibre Bragg grating sensors
复制标题
使用光纤布拉格光栅传感器对碳纤维增强塑料轴的温度和应变进行多点固化监测
DOI：
10.1080/10589759.2019.1576174
复制
发表时间：
2019-04-03
影响因子：
2.6
通讯作者：
Xie, Chen
中科院分区：
文献类型：
--
作者：
Ding, Guoping;Cao, Hao;Xie, Chen
碳纤维增强塑料（CFRP）轴具有重量轻、强度高、尺寸稳定性好和驱动效率高的特点。然而，在固化过程中形成的内在应力可能会在实际使用之前导致产品中的缺陷。采用光纤光栅传感器对CFRP轴固化过程中的温度和应变进行实时监测。以22层CFRP轴为测试样本，根据其设计确定了FBG传感器的嵌入位置。为了将所有四个FBG传感器（FBGa、FBGb、FBG 1和FBG 2）埋入CFRP轴中，制备分离心轴。FBGa和FBGb对温度和应变都敏感，而FBG 1和FBG 2被封装并且仅对温度敏感。FBGa和FBG 1埋在第一层和第二层之间，而FBGb和FBG 2埋在第九层和第十层之间。对各FBG传感器的灵敏度系数进行了标定：FBGa和FBGb的应力灵敏度系数分别为1.33 × 10（-5）和1.37 × 10（-5）pm/Pa，FBG 1和FBG 2的温度灵敏度系数分别为8.58和8.52 pm/℃。最后，利用光纤光栅传感器对CFRP轴进行了固化监测，结果表明：在第一层和第二层CFRP轴之间检测到了57.8 μ m的轴向收缩残余应变（当冷却到85摄氏度时），但第九层和第十层之间几乎为零当试样径厚比为28.4时，内表面和中间层在固化过程中的残余应变不同;采用分离芯轴将光纤光栅传感器埋入CFRP轴中是可靠的，光纤光栅传感器可以精确地检测CFRP轴在固化过程中内部温度和应变的变化。
Carbon fibre-reinforced plastic (CFRP) shafts feature lightweight, high intensity, good dimensional stability and high drive efficiency. However, built-in stress formed during curing process may cause defects in the product before actual use. In this paper, fibre Bragg grating (FBG) sensors were adopted for real-time temperature and strain monitoring of CFRP shafts while curing. A 22-layer CFRP shaft served as the test specimen and embedding positions of FBG sensors were decided based on its design. In order to bury all four FBG sensors (FBGa, FBGb, FBG1 and FBG2) into the CFRP shaft, a separating mandrel was prepared. FBGa and FBGb were sensitive to both temperature and strain, while FBG1 and FBG2 were encapsulated and only sensitive to temperature. FBGa and FBG1 were buried between the first and second layers, while FBGb and FBG2 were between the ninth and tenth layers. Sensitivity coefficient of each FBG sensor was calibrated: stress sensitivity coefficients of FBGa and FBGb were 1.33 x 10(-5) and 1.37 x 10(-5) pm/Pa; temperature sensitivity coefficients of FBG1 and FBG2 were 8.58 and 8.52 pm/celcius. Finally, cure monitoring of CFRP shaft using FBG sensors was carried out and results showed: a 57.8 mu epsilon residual strain due to axial contraction was detected between the first and second layers of CFRP shaft (when cooled to 85celcius), but that between the ninth and tenth layers was nearly zero (when cooled to 55celcius); residual strains of the inner surface and middle layers were different during curing process when specimen's diameter-thickness ratio was 28.4; it was reliable to have FBG sensors embedded into CFRP shaft using a separating mandrel; FBG sensors can precisely detect the changes of temperature and strain inside the CFRP shaft during curing process.