39 Study on AE Detection Signal of Composite Barrel Under …
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Fig. 39.8 Stage 3 waveform with a frequency of 140 kHz (Low amplitude)
Fig. 39.9 Axial compression failure of test piece
39.4 Conclusion
1. AE detection of the axial failure process of the composite cylindrical parts, analysis of AE signals, the axial pressure failure is divided into three stages, the first
stage is the elastic deformation stage of the composite matrix; the second stage
is the stage of macro cracks in the composite test piece and the macro separation
of the interface; the third stage is the stage where the composite test piece has
a large number of defects and damage. Different stages have different damage
modes and produce different characteristics of acoustic emission signals.
2. From the frequency analysis of the signal, it is known that the AE signal with a
frequency of 500 kHz, an amplitude below 60 dB, and a relatively short duration is
a waveform signal generated by the elastic deformation process of the composite
matrix during loading; the AE signal with a frequency of 140 kHz, an amplitude
below 80 dB and a duration below 1000 µm is a waveform signal of microfiber
filaments; the frequency is around 140 kHz and the amplitude is above 80 dB is
the waveform signal corresponds to the macroscopic separation of the interface
and the macroscopic crack propagation of the resin.
447
Fig. 39.8 Stage 3 waveform with a frequency of 140 kHz (Low amplitude)
Fig. 39.9 Axial compression failure of test piece
39.4 Conclusion
1. AE detection of the axial failure process of the composite cylindrical parts, analysis of AE signals, the axial pressure failure is divided into three stages, the first
stage is the elastic deformation stage of the composite matrix; the second stage
is the stage of macro cracks in the composite test piece and the macro separation
of the interface; the third stage is the stage where the composite test piece has
a large number of defects and damage. Different stages have different damage
modes and produce different characteristics of acoustic emission signals.
2. From the frequency analysis of the signal, it is known that the AE signal with a
frequency of 500 kHz, an amplitude below 60 dB, and a relatively short duration is
a waveform signal generated by the elastic deformation process of the composite
matrix during loading; the AE signal with a frequency of 140 kHz, an amplitude
below 80 dB and a duration below 1000 µm is a waveform signal of microfiber
filaments; the frequency is around 140 kHz and the amplitude is above 80 dB is
the waveform signal corresponds to the macroscopic separation of the interface
and the macroscopic crack propagation of the resin.