Integration of Networks of Sensors and Electronics for Structural Health Monitoring of Composite Materials

Table 5

Material with and without integrated inclusions: stress, amplitude, and frequency range of the first acoustic events, and their classification. The lower and upper limits of each range are the lower and upper values observed among all the experiments conducted. Only the events in a stress window of about 20 MPa have been considered. Results from laminates [16] are here reported for comparison.


Lay-up	Stress range of first AE events (MPa)	First AE Events Amplitude range (dB)	Peak Frequency of first AE events (kHz)	Event type classification based on micrographic inspections

Blank Samples	320–400	35–60	100–180	Matrix microcracking, fiber pull-out
Sample with device	89–106	50–75	150–300	Matrix micro-cracking at the sensor interface, debonding events
Blank Samples	33–43	40–50	130–170	Matrix micro-cracking, debonding,
Sample with device	10–14	43–65	150–350	Matrix micro-cracking at the sensor interface, debonding events, friction

Advances in Civil Engineering

Integration of Networks of Sensors and Electronics for Structural Health Monitoring of Composite Materials

Table 5