Materials strength and acoustic nonlinearity: case study of CFRP. Issue 1 (2nd January 2022)

• Record Type: Journal Article
• Authors: Ehrler, Julian; Solodov, Alexander; Kreutzbruck, Marc
• Is Part Of: Research in nondestructive evaluation. Volume 33:Issue 1(2022)
• Page Start: 33
• Page End: 44
• Publication Date: 2022-01-02
• Subjects: Nonlinear acoustics -- Stress-strain curve -- Tensile strength; Nondestructive testing -- Periodicals; 620.112705
• DOI: 10.1080/09349847.2021.2017531
• Languages: English
• ISSNs: 0934-9847

Abstract

ABSTRACT: Nonlinear acoustic approach is assessed as a nondestructive tool for reconstructing stress-strain curves and quantifying the ultimate tensile strength for various orientations of composite materials. It is shown that a direct use of nonlinear acoustic data requires some adjustments to be applied in the quasi-static tensile conditions. The approach is validated by the calculations using the data for the two in-plane orientations of Carbon Fiber-Reinforced Plastic (CFRP) of totally different strengths. The higher strength arrangement manifests much lower nonlinearity, while the low strength orientation indicates the higher nonlinearity. The quantitative proof-of-concept test is based on the direct measurement of the acoustic nonlinearity for the out-of-plane orientation CFRP. Far higher nonlinearity measured correlates well with the lowest strength for this orientation being a reason of characteristic materials damage in the form of delaminations.