24 Experiment Research on Tensile Process …
289
Table 24.6 The frequency distribution of the C sample (kHz)
Stage
VS150-M VS45-H VS900-M
Stage AB (elastic stage)
/
/
/
Stage BC (ascending stage of yield stage)
90–170
/
90–220
Stage DE (first half of plastic deformation stage)
80–260
/
/
Stage EF (the second half of the plastic deformation stage) /
/
/
Point F (when pulled off)
80–250
90–160 80–220
a)Hits-time
b)Energy-time
c) Amplitude-time
Fig. 24.12 C sample VS150-M acoustic emission characteristic parameter diagram
mainly distributed at 130–260 kHz, the acoustic emission signal frequency of the
VS45-H sensor is distributed at 90-200 kHz, mainly distributed at 90–180 kHz, and
the acoustic emission signal of the VS900-M sensor is distributed at 120–210 kHz,
mainly distributed at 120–70 kHz.
According to the typical waveforms and spectrum of the three sensors, the
frequency of HDPE material’s acoustic emission signal is mainly distributed between
70 and 260 kHz. In some stages, when VS150 has an acoustic emission signal, the
VS45-H and VS900-M sensors have no acoustic emission that exceeds the threshold.
Which shows that the VS150 resonant sensor can be used to detect and monitor the
HDPE material.
The following only analyzes the characteristic parameters of the acoustic emission
signals collected by VS150.
24.3.3 Characteristic Parameters of Acoustic Emission
Signals During Stretching
Acoustic emission monitoring was carried out on the tensile process of three kinds
of samples. The parameters of acoustic emission signal collection were hits, RMS
value, energy, amplitude, counts, duration time, etc. The main distribution range
of acoustic emission parameters is shown in Table 24.7. From the table, it can be
seen that the samples with preset defects have fewer hits than the samples without
preset defects, and are accompanied by the appearance of high amplitude signals.
The energy value of the sample with round notch is smaller than the energy value of
289
Table 24.6 The frequency distribution of the C sample (kHz)
Stage
VS150-M VS45-H VS900-M
Stage AB (elastic stage)
/
/
/
Stage BC (ascending stage of yield stage)
90–170
/
90–220
Stage DE (first half of plastic deformation stage)
80–260
/
/
Stage EF (the second half of the plastic deformation stage) /
/
/
Point F (when pulled off)
80–250
90–160 80–220
a)Hits-time
b)Energy-time
c) Amplitude-time
Fig. 24.12 C sample VS150-M acoustic emission characteristic parameter diagram
mainly distributed at 130–260 kHz, the acoustic emission signal frequency of the
VS45-H sensor is distributed at 90-200 kHz, mainly distributed at 90–180 kHz, and
the acoustic emission signal of the VS900-M sensor is distributed at 120–210 kHz,
mainly distributed at 120–70 kHz.
According to the typical waveforms and spectrum of the three sensors, the
frequency of HDPE material’s acoustic emission signal is mainly distributed between
70 and 260 kHz. In some stages, when VS150 has an acoustic emission signal, the
VS45-H and VS900-M sensors have no acoustic emission that exceeds the threshold.
Which shows that the VS150 resonant sensor can be used to detect and monitor the
HDPE material.
The following only analyzes the characteristic parameters of the acoustic emission
signals collected by VS150.
24.3.3 Characteristic Parameters of Acoustic Emission
Signals During Stretching
Acoustic emission monitoring was carried out on the tensile process of three kinds
of samples. The parameters of acoustic emission signal collection were hits, RMS
value, energy, amplitude, counts, duration time, etc. The main distribution range
of acoustic emission parameters is shown in Table 24.7. From the table, it can be
seen that the samples with preset defects have fewer hits than the samples without
preset defects, and are accompanied by the appearance of high amplitude signals.
The energy value of the sample with round notch is smaller than the energy value of