Sub-second laser heating of thermal impulse sensors

We have developed thermal impulse sensors to measure and record temperature and heating duration in explosive fireballs. The functionality of these sensors is similar to that of our temperature-only sensors – rare-earth ions are used to monitor temperature-induced phase changes. However, in this case two sensor materials, p-Dy:Y₂O₃ and p-Eu:ZrO₂, with different phase change kinetics are mixed. In addition, a fluorescence standard, Ho:ZrO₂, is included. Also, using laser heating, we have now reduced the shortest heating duration for our calibration measurements from the previously reported 2 s to 100 ms, and we have evaluated these sensors for temperatures between 400 °C and 900 °C, and heating times between 100 ms and 1000 ms. Using spectral matching, we determine the temperature and heating duration.