Title
High-Resolution Nondestructive Test Probes Based on Magnetoresistive Sensors
Abstract
This paper discloses two high-sensitivity probes for Eddy Current Nondestructive Test (NDT) of buried and surface defects. These probes incorporate eight and 32 magnetoresistive sensors, respectively, which are optimized for high sensitivity and spatial resolution. The signal processing and interfacing are carried out by a full-custom application-specific integrated circuit (ASIC). The ASIC signal chain performs with a thermal input-referred noise of 30 nV/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\sqrt{\text{Hz}}$</tex-math></inline-formula> at 1 kHz, with 66 mW of power consumption, in a die with 3.7×3.4 mm <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$^2$</tex-math></inline-formula> . NDT results are presented, showing that there is an increase in spatial resolution of surface defects when contrasted to prior art, enabling the probes to resolve defects with diameters of 0.44 mm, pitches of 0.6 mm, and minimum edge distance as low as 0.16 mm. The results also show that the probe for buried defects is a good all-round tool for detection of defects under cladding and multiple-plate flat junctions.
Year
DOI
Venue
2019
10.1109/TIE.2018.2879306
IEEE Transactions on Industrial Electronics
Keywords
Field
DocType
Magnetic sensors,Probes,Tunneling magnetoresistance,Surface treatment,Eddy currents,Magnetic tunneling
Signal processing,Signal chain,Control theory,Nondestructive testing,Application-specific integrated circuit,Eddy current,Engineering,Cladding (metalworking),Integrated circuit,Optoelectronics,Image resolution
Journal
Volume
Issue
ISSN
66
9
0278-0046
Citations 
PageRank 
References 
1
0.37
0
Authors
11