Inverse method to calculate material properties using an insertion loss test
AssigneeThe United States of America as represented by the Secretary of the Navy
InventorAndrew J. Hull
Life of this patent
Estimating the term…
Abstract
A method for calculating material properties of a material includes conducting two insertion loss tests of the material having a single thickness and a double thickness. These tests are conducted at a zero wavenumber. Utilizing these insertion loss tests, a dilatational wavespeed is computed. The method continues by calculating a shear wavespeed by performing three insertion loss tests of the material at single, double and triple thicknesses. These tests are conducted at a non-zero wavenumber. A shear wavespeed can be calculated from the dilatational wavespeed and these insertion loss tests. Lamé constants, Young's modulus, Poisson's ratio, and the shear modulus for the material of interest can then be calculated using the dilatational and shear wavespeeds.
Claims18
A method for calculating material properties of a material of interest comprising the steps of:
- determining a dilatational wavespeed by:
- conducting an insertion loss test of a first piece of the material having a first thickness at zero wavenumber to obtain first transfer function data;
- conducting an insertion loss test of a second piece of the material having a second thickness at zero wavenumber to obtain second transfer function data, wherein said second thickness is twice said first thickness;
- and
- calculating the dilatational wavespeed from said first transfer function and said second transfer function;
- determining a shear wavespeed by:
- conducting an insertion loss test of a first piece of the material having a first thickness at a non-zero wavenumber to obtain first shear transfer function data;
- conducting an insertion loss test of a second piece of the material having a second thickness at a non-zero wavenumber to obtain second shear transfer function data, wherein said second thickness is twice said first thickness;
- conducting an insertion loss test of a third piece of the material having a third thickness at zero wavenumber to obtain third shear transfer function data, wherein said third thickness is three times said first thickness;
- calculating the shear wavespeed from said first shear transfer function, said second shear transfer function, said third shear transfer function and said dilatational wavespeed;
- and
- providing said calculated shear wavespeed and said calculated dilatational wavespeed from said steps of calculating as the material properties.
A method for obtaining the dilatational wavespeed of a material comprising the steps of:
- conducting an insertion loss test of a first piece of the material having a first thickness at zero wavenumber to obtain first transfer function data;
- conducting an insertion loss test of a second piece of the material having a first thickness at zero wavenumber to obtain second transfer function data;
- calculating the dilatational wavespeed from said first transfer function and said second transfer function;
- and
- providing the calculated dilatational wavespeed as one of the material properties.
A method for calculating material properties of a material of interest comprising the steps of:
- determining a dilatational wavespeed by:
- conducting an insertion loss test of a first piece of the material having a first thickness at zero wavenumber to obtain first transfer function data;
- conducting an insertion loss test of a second piece of the material having a second thickness at zero wavenumber to obtain second transfer function data, wherein said second thickness is twice said first thickness;
- and
- calculating the dilatational wavespeed from said first transfer function and said second transfer function;
- determining a shear wavespeed by:
- conducting an insertion loss test of a first piece of the material having a first thickness at a non-zero wavenumber to obtain first shear transfer function data;
- conducting an insertion loss test of a second piece of the material having a second thickness at a non-zero wavenumber to obtain second shear transfer function data, wherein said second thickness is twice said first thickness;
- conducting an insertion loss test of a third piece of the material having a third thickness at zero wavenumber to obtain third shear transfer function data, wherein said third thickness is three times said first thickness;
- calculating the shear wavespeed from said first shear transfer function, said second shear transfer function, said third shear transfer function and said dilatational wavespeed;
- and
- providing plots of said transfer functions from said steps of conducting insertion loss tests.
Dependencies are inferred from the claim text.