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When most of ceramics are fractured, the emission of various particles, for example photons, electrons, ions and so on, is observed. The emission has been expected to be a fast and microscopic analysis method for the fracture process. Although the emission should be related to the mechanical property, few studies have been reported on a relationship between them. In this study, the intensity of the particle emission and the strain energy released at the fracture were simultaneously measured to clarify the relationship between the mechanical property and the emission. Silica glass was used as a sample to avoid effects of microstructure or anisotropy. The sample was fractured by three-point bending in vacuum at 10-5 Pa and at room temperature. The fracture load was measured to estimate the released strain energy. The charged particles and photons emitted during the fracture were simultaneously detected by channeltoron electron multiplier and photomultiplier tube, and counted by using multi-channel scaler with a gate time of 1 ms. Before the fracture, no emission of the particles was observed. The intensity of the negatively charged particle emission (NeE) showed a peak at the fracture, followed by some bursts of the NeE. The intensities of infrared and visible photon emissions (PEs) also showed peaks at the fracture, but then decayed exponentially to noise level. To study the relationship between the mechanical property and the emission, the peak intensity of each particle emission was compared to the released strain energy. In the case of the PE, both of the intensities of the infrared and visible PEs were positively correlated with the strain energy. This shows that a part of the released strain energy is dissipated for the PE. In contrast, there was no correlation between the intensity of the NeE and the strain energy. Thus, the process of NeE appears to be different from that of the PE. Based upon the results, the emission process of each particle is discussed. |