An optical fiber sensing method was developed for prestress measurements of glass-metal seals. A fiber Bragg grating sensor was embedded in a hole in the sealing glass. The glass was then heated to melting, cooled and solidified so that the optical fiber sensor, the glass and the metal shell were sealed together. The fiber sensor gave real-time measurements of the sealing temperature during the sealing. The changes of the Bragg wavelength were used to measure the axial strain along the measurement path in the glass seal. The global stress distribution in the glass was then calculated by a finite element analysis. Tests show that the fiber sensor can monitor the temperature and stress during the sealing process and an optimized sealing process can be achieved by using prestress measurements in the glass as an indicator.
摘要 为实现对玻璃中预应力的测量, 该文提出了一种基于光纤传感的玻璃封接预应力测量方法。将光纤Bragg光栅传感器植入封接玻璃预留孔中, 加热使玻璃熔融, 再冷却固化从而使光纤传感器、玻璃、金属同时烧结在一起。通过光纤传感信号的实时监测, 实现了对封接温度的实时测量。通过光纤传感信号的变化, 计算出了封接玻璃中测量路径的轴向压缩应变, 结合有限元分析得到玻璃中的全局应力分布。实验结果表明：光纤传感器可实现对封接过程温度和应力的监测, 以玻璃中预应力为指标可以实现对封接工艺的优化。