Patent ID: 6609428
Filing Date: 2003-08-26
Classification: G01N

Abstract:
A method for estimating the real and imaginary Poisson's ratio of a material comprising the steps of:providing a first specimen of the material; providing an excitation frequency of interest; installing said first specimen in a first test apparatus with a first end of said first specimen being joined to a reciprocating motion source and a second end of said first specimen having a mass joined thereto; subjecting said first specimen to reciprocating motion at the excitation frequency from said reciprocating motion source; recording a first set of accelerations at said first specimen first end; recording a second set of accelerations at said first specimen second end; calculating the Young's modulus of the material from said obtained first set of accelerations and said obtained second set of accelerations; providing a second specimen of the material having a cylindrical configuration; installing said second specimen in a second test apparatus with a first end of said second specimen being joined to a reciprocating rotational motion source and a second end of said second specimen having a rotational inertia joined thereto; subjecting said second specimen to reciprocating rotational motion at the excitation frequency from said reciprocating motion source; recording a third set of accelerations at said second specimen first end; recording a fourth set of accelerations at said second specimen second end; calculating the shear modulus of the material from said obtained third set of accelerations and said obtained fourth set of accelerations; and calculating the Poisson's ratio of the material at the excitation frequency from said calculated Young's modulus and said calculated shear modulus.