Real-Time Corrosion Monitoring of Aircraft Structures with Prognostic Applications

Douglas Brown, Duane Darr, Jefferey Morse, and Bernard Laskowski
Submission Type: 
Full Paper
Supporting Agencies (optional): 
US Air Force
phmc_12_018.pdf3.14 MBSeptember 20, 2012 - 1:45pm

This paper presents the theory and experimental validation of a Structural Health Management (SHM) system for monitoring corrosion. Corrosion measurements are acquired using a micro-sized Linear Polarization Resistance (uLPR) sensor. The uLPR sensor is based on conventional macro-sized Linear Polarization Resistance (LPR) sensors with the additional benefit of a reduced form factor making it a viable and economical candidate for remote corrosion monitoring of high value structures, such as buildings, bridges, or aircraft.

A series of experiments were conducted to evaluate the uLPR sensor for AA 7075-T6, a common alloy used in aircraft structures. Twelve corrosion coupons were placed alongside twenty-four uLPR sensors in a series of accelerated tests. LPR measurements were sampled once per minute and converted to a corrosion rate using the algorithms presented in this paper. At the end of the experiment, pit-depth due to corrosion was computed from each uLPR sensor and compared with the control coupons.

The paper concludes with a feasibility study for the uLPR sensor in prognostic applications. Simultaneous evaluation of twenty-four uLPR sensors provided a stochastic data set appropriate for prognostics. RUL estimates were computed a-posteriori for three separate failure thresholds. The results demonstrate the effectiveness of the sensor as an efficient and practical approach to measuring pit-depth for aircraft structures, such as AA 7075-T6, and provide feasibility for its use in prognostic applications.

Publication Year: 
Publication Volume: 
Publication Control Number: 
Page Count: 
Submission Keywords: 
structural health monitoring
Submission Topic Areas: 
Component-level PHM
Structural health monitoring
Submitted by: 

follow us

PHM Society on Facebook Follow PHM Society on Twitter PHM Society on LinkedIn PHM Society RSS News Feed