2. Structure and Principle
3. Material Property
4. Simulation and Experiments
- Step 1—curing process: The initial state or stress-free state of the sensor appeared at 60 °C where the curing process started, and the P1 was located at position 0 in Figure 10a.
- Step 3—room temperature retention: The compression of glass decreased due to stress relaxation, and P1 slightly moved in the negative x direction, which led to the decrease of um and increase of d1 (Figure 10c). The offset and sensitivity decreased.
- Step 4—starting point of high temperature: The model expanded, and the point P1 moved in the negative x direction substantially, which caused the decrease of um and increase of d1 (Figure 10d). Therefore, the offset and sensitivity continued to decrease.
- Step 5—ending point of high temperature: During the thermal treatment process, the tension on the glass decreased due to stress relaxation, and P1 slightly moved in the positive x direction to result in a higher offset and sensitivity (Figure 10e).
- Step 6—cooling to room temperature again: The model shrank, and the shrinkage included both the thermal part in step 4 and additional shrinkage value generated by strong viscoelasticity at 125 °C. Hence, the point P1 moved to the right position 1 (Figure 10f). Consequently, the offset and sensitivity at this stage were larger than those of Figure 10b.
- Step 7—room temperature retention again: The offset and sensitivity decreased, due to stress relaxation, but they were still larger than those in Figure 10c. This indicated that the offset level is influenced by thermal treatment, so higher-temperature dwells lead to greater offset and sensitivity (Figure 10g).
Conflicts of Interest
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|Material||Young’s Modulus (Gpa)||Poisson Ratio||CTE (ppm/°C)|
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