Anisotropy of NEWS damage parameters in CFRP composite

0465265 - ÚT 2017 DE eng A - Abstrakt
Převorovský, Zdeněk - Kober, Jan - Tokar, Daniel - Krofta, Josef
Anisotropy of NEWS damage parameters in CFRP composite.
WCNDT 2016 BOOK of ABSTRACTS Munich. 2016. s. 9-9.
[World Conference on Non-Destructive Testing /19./. 13.06.2016-17.06.2016, Mnichov]
Institucionální podpora: RVO:61388998
Klíčová slova: carbon fiber composites * anisotropy * damage detection * nonlinear elastic wave spectroscopy
Kód oboru RIV: BI - Akustika a kmity
https://www.wcndt2016.com/Programme/show/Mo-1-B-3

Variety of NEWS techniques provide for sensitive detection and imaging of incipient damage like microcracks, delamination, weakening of adhesive bonds, etc.Suitable configurations of transducers enable also location of defective zones characterized by appropriate non-linear parameters obtained by NEWS techniques along different wave paths. In composites, exhibiting often high anisotropy of wave velocity, attenuation etc., the correct evaluation of nonlinearity is problematic. For that purpose we designed a multi-directional ultrasonic array probe with 8 to 32 piezoelectric transducers multiplexed as transmitters and receivers. The probe was used to obtain directivity patterns of wave celerity, attenuation, and nonlinearity parameters on CFRP plates, both intact and damaged by impact and artificial delamination. The probe can be efficiently applied not only to plates but also to curved surfaces. Three NEWS methods were applied: Time Reversal-NEWS, nonlinear wave modulation spectroscopy (NWMS), and scale subtraction method (SSM). Respecting of material anisotropy contributes to more reliable determination and location of defects by NEWS methods.
Trvalý link: http://hdl.handle.net/11104/0266412