Campus Units
Aerospace Engineering, Center for Nondestructive Evaluation (CNDE)
Document Type
Article
Publication Version
Published Version
Publication Date
2015
Journal or Book Title
The Journal of the Acoustical Society of America
Volume
137
Issue
2
First Page
617
Last Page
624
DOI
10.1121/1.4906165
Abstract
This paper presents the study of non-classical nonlinear response of fiber-reinforced composites. Nonlinear elastic wave methods such as nonlinearresonant ultrasound spectroscopy (NRUS) and nonlinear wave modulation spectroscopy have been used earlier to detect damages in several materials. It was observed that applying these techniques to composites materials becomes difficult due to the significant inherent baseline nonlinearity. Understanding the non-classical nonlinear nature of the composites plays a vital role in implementing nonlinear acoustic techniques for material characterization as well as qualitative nondestructive testing of composites. Since fiber reinforced composites are orthotropic in nature, the baseline response variation with fiber orientation is very important. This work explores the nature of the inherent nonlinearity by performing nonlinear resonant spectroscopy (NRS) in intact unidirectional carbon/epoxy samples with different fiber orientations with respect to major axis of the sample. Factors such as frequency shifts, modal damping ratio, and higher harmonics were analyzed to explore the non-classical nonlinear nature of these materials. Conclusions were drawn based on the experimental observations.
Copyright Owner
Acoustical Society of America
Copyright Date
2015
Language
en
File Format
application/pdf
Recommended Citation
Chakrapani, Sunil Kishore; Barnard, Daniel J.; and Dayal, Vinay, "Influence of fiber orientation on the inherent acoustic nonlinearity in carbon fiber reinforced composites" (2015). Aerospace Engineering Publications. 80.
https://lib.dr.iastate.edu/aere_pubs/80
Comments
This article is published as Chakrapani, Sunil Kishore, Daniel J. Barnard, and Vinay Dayal. "Influence of fiber orientation on the inherent acoustic nonlinearity in carbon fiber reinforced composites." The Journal of the Acoustical Society of America 137, no. 2 (2015): 617-624. DOI: 10.1121/1.4906165. Posted with permission.