Topic
Acoustic emission
About: Acoustic emission is a research topic. Over the lifetime, 16293 publications have been published within this topic receiving 211456 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: In this paper, the authors focus on the experimental investigation of impact damage resistance in hybrid composite laminates with online acoustic emission (AE) monitoring and evaluate the indentation response by measuring peak force, absorbed energy and linear stiffness.
Abstract: This paper focuses on the experimental investigation of impact damage resistance in hybrid composite laminates. In this case, the low velocity impact behaviour of quasi-isotropic glass/epoxy, glass/basalt/epoxy (G/B/G, B/G/B) and glass/carbon/epoxy (G/C/G, C/G/C) composite laminates was simulated by carrying out quasi-static indentation (QSI) tests with online acoustic emission (AE) monitoring. The dent depth, back surface crack size and load-deflection behaviors were examined and there is no distinct differences could be seen between low velocity impact tests and quasi-static indentation tests. The QSI tests were performed on specimens with rectangular section, of size 150 mm x 100 mm, which were loaded at the centre by a hemispherical steel indenter with 12.7 mm diameter. The indentation response was evaluated by measuring peak force, absorbed energy and linear stiffness. The residual strength of the laminates following indentation was measured by testing them under compression load in a 100 kN universal testing machine, once again with AE monitoring. AE parameters, such as amplitude, rise time, cumulative counts and cumulative energy were considered for monitoring damage progression during quasi-static indentation loading. Also other parameters linked to AE monitoring, such as the rise angle (RA) and Felicity ratio (FR) were measured for evaluating the damage resistance in each cycle of indentation. In addition, sentry function was also computed based on the combination of mechanical strain energy accumulated in the materials and of the acoustic energy propagates by fracture events made it possible to evaluate the amount of induced damage. These results showed that the combination of glass and carbon fibres in glass/carbon/epoxy (C/G/C) laminates improved their interlaminar shear strength at a level well above the other configurations tested.
66 citations
TL;DR: Two well-known nonlinear Kalman Filtering algorithms are presented to estimate the location of AE sources in anisotropic panels and it is shown that both EKF and UKF can provide a confidence interval of the estimated AE source location and can account for uncertainty in time of flight measurements.
66 citations
TL;DR: In this article, the authors simulated hydrogen embrittlement with ammonium thiocyanate media test and showed that three stages of the damage mechanism are identified with different acoustic activities.
66 citations
TL;DR: In this paper, a new acoustic emission (AE) diagnostic technique, for the study of fatigue cracks nucleation and propagation on steel, was investigated using the fractal analysis, and the box-counting method (BCM) in particular.
66 citations
TL;DR: In this article, an in-house developed algorithm is proposed, which utilises the results of unsupervised pattern recognition classification of acoustic emission data, and correlation between clusters and specific material failure modes was achieved, using algorithm results and cluster activation parameters.
Abstract: The present work aims toward the application of an innovative methodology for the analysis of acoustic emission (AE) activity monitored during the quasistatic tensile loading of centre-hole carbon/carbon. An in-house developed algorithm is proposed, which utilises the results of unsupervised pattern recognition classification of AE data. Correlation between clusters and specific material failure modes was achieved, using algorithm results and cluster activation parameters. During the analysis a dependence of AE activity on the hole diameter was observed.
66 citations