Acta Univ. Agric. Silvic. Mendelianae Brun. 2018, 66, 1217-1224

https://doi.org/10.11118/actaun201866051217
Published online 2018-10-29

Analysis of Surface Defects in Composites Using Digital Image Correlation and Acoustic Emission

Jaroslav Začal1, Petr Dostál1, Jakub Rozlivka1, Martin Brabec2

1Department of Technology and Automobile Transport, Faculty of Agronomy, Mendel University in Brno, Zemědělská 1, 613 00 Brno, Czech Republic
2Department of Wood Science, Faculty of Forestry and Wood Technology, Mendel University in Brno, Zemědělská 3, 613 00 Brno, Czech Republic

This work employs the acoustic emission (AE) method for material state monitoring. AE presents a non‑destructive evaluation technique, which could be used for detection of microstructural changes in composite material. Work describes the process of acquisition of AE in tensile loading of carbon composite materials. In course of tensile stress, the composite was monitored with optical method, applying principles of digital image correction (DIC). Optical stereovision method enables calculation of field shift and field of proportional deformation at composite surface. The objective is analysis of damage in carbon composite materials and employ the methodology of AE signal processing for facilitation of early damage diagnostics and prediction of structural failure. For this purpose, the experimental setup was designed to obtain results from 50 nominally identical composite samples in tensile loading test. Force load applied on samples was synchronically recorded along with AE and image data. Experimental data were subsequently analysed in a way enabling the description of typical phenomena in course of every measurement. Results show that observation of AE sources could be employed in facilitation of early damage diagnostics and establishment of failure prognosis. It is about internal changes in composite material.

Funding

The research has been supported by the project TP 6/2017: Defectoscopic quality assessment of technical and organic materials; financed by IGA AF MENDELU.

References

18 live references