考虑光纤Bragg光栅(FBG)粘接层的材料特性会直接影响FBG传感器的应变测量精度,本文根据粘接层应变传递模型,结合应变传递系数K的表达公式,在确定粘接层结构尺寸参数的前提下,仿真分析了粘接层弹性模量对应变传递系数K的影响。分析结果表明,金属材料的应变传递效率明显优于有机胶的应变传递效率。进行了传递效果评价对比试验,结果表明,铅粘接层的应变传递系数维持在0.98左右,环氧树脂粘接层的应变传递系数维持在0.90左右,前者比后者的应变传递效率提高了约8.9%,显示将粘接材料由环氧树脂改进为铅后,可大大提高应变测量的精度,更加充分发挥光纤器件自身优越的应变测量能力。
As material characteristics of a bond layer directly affect the measurement accuracy of Fiber Bragg Grating(FBG) strain sensors,this paper simulates the impact of elastic modulus of the bond layer materials on strain transfer coefficient K according to the bond layer strain transfer model and the formula of strain transfer coefficient K under the premise of determining the structure size parameters.The results show that the strain transfer efficiency of metal is superior obviously to that of the organic adhesive.A contrast test is carried out.Test results indicate that the strain transfer coefficient K of the lead maintains a level of 0.98 while that of epoxy maintains about 0.90,and the former′s transfer efficiency has increased by 8.9% as compared with that of the latter.By replacing epoxy with the lead,it can greatly improve the strain measurement precision,and can more fully exert fiber optic sensors′ strain measurement ability.