TY - JOUR

T1 - In-depth study of direct and derived acoustic emission parameters and their information content for classifying lubricated tribological sliding contacts

AU - Strablegg, Christopher

AU - Summer, Florian

AU - Renhart, Philipp

AU - Pusterhofer, Michael

AU - Grün, Florian

N1 - Publisher Copyright: © 2023 The Authors

PY - 2023/12

Y1 - 2023/12

N2 - Acoustic signals (AE) have become a valuable tool for monitoring various tribological systems. This study investigates three key tribological behaviors: the initial running-in process, severe wear, and the lubrication state of journal bearings using four AE postprocessing methods. These methods are friction power-scaled quadratic mean (SRMS), power spectrum (PSD), normalized power spectrum (nPSD), and a statistical hit-rate (HR) analysis of the raw AE signal. The research draws on data from four tests conducted in three set-ups: Ring-on-Disc (RoD), Ring-on-Liner (RoL), and Journal-bearing-adapter (JBA) test configurations. AE measurements were taken at both 1 Hz and 1 kHz for the quadratic mean value (RMS), as well as at 900 kHz for short time intervals during each test to capture the raw signal data. In conjunction with other measured parameters like friction coefficient, temperature, contact potential, and wear, we establish correlations between the acoustic parameters and tribological behaviors. The findings indicate that SRMS and nPSD are valuable for identifying the end of the initial running-in phase. All four methods are effective in recognizing high wear states, with nPSD and HR even distinguishing between different wear phenomena. The lubrication state of journal bearings is best assessed using nPSD, allowing users to monitor certain geometric changes in the bearing.

AB - Acoustic signals (AE) have become a valuable tool for monitoring various tribological systems. This study investigates three key tribological behaviors: the initial running-in process, severe wear, and the lubrication state of journal bearings using four AE postprocessing methods. These methods are friction power-scaled quadratic mean (SRMS), power spectrum (PSD), normalized power spectrum (nPSD), and a statistical hit-rate (HR) analysis of the raw AE signal. The research draws on data from four tests conducted in three set-ups: Ring-on-Disc (RoD), Ring-on-Liner (RoL), and Journal-bearing-adapter (JBA) test configurations. AE measurements were taken at both 1 Hz and 1 kHz for the quadratic mean value (RMS), as well as at 900 kHz for short time intervals during each test to capture the raw signal data. In conjunction with other measured parameters like friction coefficient, temperature, contact potential, and wear, we establish correlations between the acoustic parameters and tribological behaviors. The findings indicate that SRMS and nPSD are valuable for identifying the end of the initial running-in phase. All four methods are effective in recognizing high wear states, with nPSD and HR even distinguishing between different wear phenomena. The lubrication state of journal bearings is best assessed using nPSD, allowing users to monitor certain geometric changes in the bearing.

UR - http://www.scopus.com/inward/record.url?scp=85174403335&partnerID=8YFLogxK

U2 - 10.1016/j.triboint.2023.109028

DO - 10.1016/j.triboint.2023.109028

M3 - Article

VL - 2023

JO - Tribology International

JF - Tribology International

SN - 0301-679X

IS - Vol.190*December

M1 - 109028

ER -