Abstract Temperature monitoring of braze seam with high sensitivity and fast response is essential for safe working of a joint. Herein, a non-contact optical thermometry for joint is designed. The Yb3+/Er3+:Y2O3 micro-crystals were prepared and mixed into bismuth borate glass to bond Al2O3 ceramics. After brazing, Y2O3 particles still preserve perfect crystal structure, and its addition widens the thickness of braze seam. The obtained shear strength of joint is up to 83.5 MPa. Under 980 nm excitation, 2H11/2 and 4S3/2 levels of Er3+ ion in braze seam are thermally coupled levels and show excellent temperature dependent characteristic. The temperature sensing sensitivity is superior and the maximum values of absolute sensitivity and relative sensitivity are 0.0182 K-1 and 0.51 %K-1, respectively. This optical thermometry for brazing seam will further promote the joint reliability research and provide new strategies to measure the temperature in micro-region of component.

中文翻译：

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用于高灵敏度检测钎焊缝温度的功能性 Al2O3/Al2O3 接头的设计

摘要 高灵敏度、快速响应的钎焊缝温度监测对于接头的安全工作至关重要。在此，设计了一种用于关节的非接触式光学测温。制备 Yb3+/Er3+:Y2O3 微晶并将其混合到硼酸铋玻璃中以结合 Al2O3 陶瓷。钎焊后，Y2O3 颗粒仍然保持完美的晶体结构，并且它的加入扩大了钎焊缝的厚度。获得的接头剪切强度高达83.5 MPa。在 980 nm 激发下，焊缝中 Er3+ 离子的 2H11/2 和 4S3/2 能级是热耦合能级，表现出优异的温度相关特性。感温灵敏度优越，绝对灵敏度和相对灵敏度的最大值分别为0.0182 K-1和0.51 %K-1。