Heat emission patterns in the infrared spectrum were discovered in ice subjected to cyclic loading. The ice plates used in the tests had a rectangular shape of 13 x 19 cm and a thickness of 2 cm. The plates were frozen to the platen of the testing apparatus to form a cantilever beam and were vibrated over a frequency range from n.5 to 5 kHz at an ambient temperature of -4°C. The surface heat patterns were scanned by two thermal imaging systems with spectral hand passes of 2-5.6 pm and 8-14 μm, and the heat patterns were recorded on Polaroid film and on videotape. The heat emission patterns first appeared at the fixed end of the ice plate and migrated gradually to the free end. The temperature difference between the ends was found to depend on the duration and frequency of excitation. The results of these tests indicate that vihrothermography can have wide areas of practical application in the study of the origin and growth of defects, recrystallization, fatigue, and failure processes in ice.
Anatoly M. Fish,
Stephen J. Marshall,
Richard H. Munis,
"Thermal Patterns in Ice Under Dynamic Loading", Proc. SPIE 0430, Infrared Technology IX, (19 January 1984); doi: 10.1117/12.936394; https://doi.org/10.1117/12.936394