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为解决胶封布拉格光纤光栅 (FBG) 传感器在飞行器恶劣环境下难以长期存活的问题, 提出一种基于一步超声波焊接的金属化方法, 实现了FBG的柱体金属化封装.根据热弹性力学建立了温度传感的理论模型, 对金属化封装FBG内部产生的热应力进行了分析, 研究了封装后FBG的温度传感重复性, 并利用扫描电子显微镜 (SEM) 和能谱分析仪 (EDS) 对其截面进行形貌观测和元素分析.结果表明, 在20～55℃内的各个温度稳定点, 金属化封装FBG的输出中心波长漂移标准差仅为2.1 pm, 波长重复性好, 相关系数为0.999, 温度敏感系数为36.38 pm/℃, 是裸FBG的3.27倍, 与理论分析结果一致.SEM图显示FBG与焊接金属基体结合紧密;EDS定性分析了焊接金属合金主要是由Sn元素组成.因此, 采用柱体金属化封装方法能够很好地解决FBG温度传感过程中对轴向应变敏感的问题, 具有快速的温度响应特性, 在航空航天结构健康监测领域中具有重要的应用价值.“,”In order to solve the problem of long-term survival for sealed FBG sensor working in harsh environment of aircraft, a metallic packaging method based on one-step ultrasonic welding was proposed, and the cylinder metallic packaging of the FBG sensor was realized. Based on the thermal elastic mechanics, the theoretical model of temperature sensing was put forward to analyze the thermal stress generated inside the metallic packaged FBG. The repeatability of the temperature sensing of the sealed FBG sensor was also studied. The scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS) were used to observe the cross-sectional morphology of metallic packaged FBG sensor and analyze its elements. The results reveal that at the thermally stable points in the range of 20～55℃, the standard deviation of metallic packaged FBG sensor output center wavelength drift is only 2.1 pm, which indicates that the wavelength repeatability is good, and the correlation coefficient is 0.999, the temperature sensitivity coefficient of the metal-packaged FBG is 34.38 pm/°C, which is 3.27 times of that for bare FBG and is consistent with the theoretical analysis result. The SEM image shows that the FBG is bonded with the welding metal substrate tightly. The EDS qualitative analysis shows that the welding metal alloy is mainly composed of element Sn. The proposed cylinder metallic packaging method can solve the problem of sensitiveness to axial strain, has fast temperature response characteristic, and has important application value in the structural health monitoring field of aeronautics and astronautics.