Method and apparatus for analyzing material properties using reflected ultrasound
US5038787A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 10, 1988 |
| Grant date | Aug 13, 1991 |
| Priority date | — |
| Expiry date | Aug 10, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2291/269
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus which assesses the mechanical properties of a material by launching an ultrasound signal at the material while varying the angle of incidence and analyzing the amplitude of the ultrasound wave reflected by the material. The method and apparatus correlates extrema (maxima or minima inflection points) in the reflected angle with the angle of incidence of the transmitted signal to identify critical angles of incidence. The velocity of the pressure wave in the material has been found to be a function of a first critical angle corresponding to a first maxima as the angle of incidence is increased in the range 0.degree.-90.degree.. The velocity of the shear wave in the material has been found to be a function of a second critical angle corresponding to a second maxima following the first maxima. Young's modulus of elasticity, Poisson's modulus, and density can be approximated using the velocity of the pressure wave and shear wave for isotropic materials. A third critical angle corresponding to a minima after the first critical angle (reflected amplitude approaching o) has been found particularly useful in conjunction with the first and second critical angles in ass…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.