The critical exponents of fracture precursors
نویسندگان
چکیده
The acoustic emission of fracture precursors is measured in heterogeneous materials. The statistical behaviour of these precursors is studied as a function of the load features and the geometry. We find that the time interval δt between events (precursors) and events energies ε are power law distributed and that the exponents of these power laws depend on the load history and on the material. In contrast, the cumulated acoustic energy E presents a critical divergency near the breaking time τ which is E ∼ ( τ−t τ ) −γ . The positive exponent γ is independent, within error bars, by all the experimental parameters. PACS: 62.20.Mk, 05.20.-y, 81.40.Np
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تاریخ انتشار 1999