Abstract

Obtaining broadband dynamic mechanical properties of viscoelastic materials is challenging. Commercially available characterization equipment is typically limited to about 500 Hz. Ultrasonic testing is a common strategy but requires time-temperature superposition extrapolation to audible frequencies. These techniques are indirect and sensitive to inhomogeneities. Modal methods do not yield broadband data and can fail for materials with high loss factors. A new relatively simple characterization method, relying on bending wave excitation and laser Doppler vibrometer measurement, is proposed. Complex elastic moduli and phase speeds are now attainable over the entire range of building acoustics frequencies. The materials under test are an array of polyurea aerogels with fixed chemical composition but tailorable nanomorphologies. Low cost and ease of synthesis add appeal to materials already noted for their sound transmission loss performance [4].

Department(s)

Chemistry

Publication Status

Open Access

Comments

National Science Foundation, Grant 1636306/1661246/172043

Keywords and Phrases

Bending; Characterization; Damping; Flexural; Transmission

International Standard Book Number (ISBN)

978-393929615-7

International Standard Serial Number (ISSN)

2415-1599; 2226-7808

Document Type

Article - Conference proceedings

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2024 RWTH Publications, All rights reserved.

Publication Date

01 Jan 2019

Included in

Chemistry Commons

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