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Title: MEMS Acoustic Emission Sensors
This paper presents a review of state-of-the-art micro-electro-mechanical-systems (MEMS) acoustic emission (AE) sensors. MEMS AE sensors are designed to detect active defects in materials with the transduction mechanisms of piezoresistivity, capacitance or piezoelectricity. The majority of MEMS AE sensors are designed as resonators to improve the signal-to-noise ratio. The fundamental design variables of MEMS AE sensors include resonant frequency, bandwidth/quality factor and sensitivity. Micromachining methods have the flexibility to tune the sensor frequency to a particular range, which is important, as the frequency of AE signal depends on defect modes, constitutive properties and structural composition. This paper summarizes the properties of MEMS AE sensors, their design specifications and applications for detecting the simulated and real AE sources and discusses the future outlook.  more » « less
Award ID(s):
2016444
PAR ID:
10230401
Author(s) / Creator(s):
Date Published:
Journal Name:
Applied Sciences
Volume:
10
Issue:
24
ISSN:
2076-3417
Page Range / eLocation ID:
8966
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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