Resonant nonlinear ultrasound spectroscopy

US6330827A · kind A · utility

Assignee

• The Regents of the University of California · US

Inventors

• Paul A. Johnson · Santa Fe, US
• James A. TenCate · Los Alamos, US
• Robert Guyer · Reno, US
• Koen Van Den Abeele · Sint-Niklaas, BE

Key dates

• Filing date: Nov 19, 1999
• Grant date: Dec 18, 2001
• Expiry date: Nov 19, 2019

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N2291/2626
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Components with defects are identified from the response to strains applied at acoustic and ultrasound frequencies. The relative resonance frequency shift .vertline..DELTA..function./.function..sub.0.vertline., is determined as a function of applied strain amplitude for an acceptable component, where .function..sub.0 is the frequency of the resonance peak at the lowest amplitude of applied strain and .DELTA..function. is the frequency shift of the resonance peak of a selected mode to determine a reference relationship. Then, the relative resonance frequency shift .vertline..DELTA..function./.function..sub.0 is determined as a function of applied strain for a component under test, where fo .function..sub.0 the frequency of the resonance peak at the lowest amplitude of applied strain and .DELTA..function. is the frequency shift of the resonance peak to determine a quality test relationship. The reference relationship is compared with the quality test relationship to determine the presence of defects in the component under test.