| Title |
Study of acoustic emission signals during crack propagation in multiscale nano-composites / |
| Authors |
Subadra, Sharath P ; Kek, Tomaž ; Bergant, Zoran ; Griškevičius, Paulius |
| DOI |
10.5755/j01.mech.4.24.20535 |
| Full Text |
|
| Is Part of |
Mechanika.. Kaunas : KTU. 2018, vol. 24, no. 4, p. 391-398.. ISSN 1392-1207. eISSN 2029-6983 |
| Keywords [eng] |
polymer composites ; fracture toughness ; acoustic test ; modal analysis |
| Abstract [eng] |
Polymer composites are gaining wide acceptance in industries for their high in-plane specific stiffness and specific strength. The damage these materials undergo are quite unique, and could limit or even prolong their usage on an even wider scale in critical sectors like the wind industry. De-lamination in laminated composites is a seri-ous issue and could be attributed to de-bonding, matrix cracking and fibre rupture. Factors leading to delamination are weak fibre/matrix interface and brittle nature of the resins. Studies have shown that delamination could be controlled to some extend by altering the internal structure of the composites. Addition of nanotubes (CNTs) is one widely accepted method, for it has been shown that they bridge the crack growth. Six specimens classed into two groups-first without nanotubes (1.n, where 𝑛=1,2,3) and second with nanotubes (2.n)- where fabricated as per ASTM 5528. Delamination was simulated in the opening mode (mode-I) with simultaneous acoustic signal registra-tion. Post experiments, the influence of CNTs on the frac-ture toughness was studied and modal acoustic emission analysis carried out on the signals by generating wavelet transforms. The results showed a considerable increase in inter-laminar fracture toughness GIc, but at the expense of a reduced load bearing capacity. Signal analysis based on modes where found to be more promising when compared to peak frequency analysis. |
| Published |
Kaunas : KTU |
| Type |
Journal article |
| Language |
English |
| Publication date |
2018 |
| CC license |
|
