title: Sensitivity of the resonant ultrasound spectroscopy to weak gradients of elastic properties.
abstract: The applicability of resonant ultrasound spectroscopy on materials with weak spatial gradients in elastic coefficients and density is analyzed. It is shown that such gradients do not affect measurably the resonant spectrum but have a significant impact on the modal shapes. A numerical inverse procedure is proposed to explore the possibility of reconstructing the gradients from experimentally obtained modal shapes. This procedure is tested on synthetic data and applied to determine the gradient of the shear modulus in a continuously graded silicon nitride ceramic material. The results are in a good agreement with the gradient calculated for the examined material theoretically as well as with the results of other experimental methods.
authors.affiliation: Institute of Thermomechanics, Academy of Sciences of the Czech Republic, Dolejškova 5, 18200 Prague; Czech Republic. hseiner@it.cas.cz
authors.forename: Hanuš
authors.initials: H
authors.lastname: Seiner
authors.forename: Petr
authors.initials: P
authors.lastname: Sedlák
authors.forename: Lucie
authors.initials: L
authors.lastname: Bodnárová
authors.forename: Alena
authors.initials: A
authors.lastname: Kruisová
authors.forename: Michal
authors.initials: M
authors.lastname: Landa
authors.forename: Angel
authors.initials: A
authors.lastname: de Pablos
authors.forename: Manuel
authors.initials: M
authors.lastname: Belmonte