固体のマイクロ破壊に伴う光パルスとそのスペクトルの測定 (第2報)

各種固体材料

抄録

It was reported in the former paper that, when a fused quartz is scratched by an abrasive grain, a series of pit (5-30μm) array can be formed and a series of light pulse array corresponding to the pit array is found to emit. In this report, various solid samples were subjected to observe the pulses and to estimate the momentary temperatures. The temperature was found to have a relation to the thermal conductivity of the material. Silicate materials (SiO₂ : fused quartz, single crystal and Pyrex glass), which have low thermal conductivities, show rather high temperature, even emitting line spectra near 300nm suggesting desorption of O₂ molecules from SiO₂. Diamond show rather low temperature, about 1500°C inspite of having the highest hardness, it is because the thermal conductivity κ is 2000W/mK, 1500 times that of the fused quartz. Metals having brittle nature emit pulses, however, they show rather low temperatures reflecting their high κ.