Accession Number : ADD012960

Title :   Properties of Composite Laminates Using Leaky Lamb Waves.

Descriptive Note : Patent,

Corporate Author : DEPARTMENT OF THE AIR FORCE WASHINGTON DC

Personal Author(s) : Chimenti,Dale E ; Bar-Cohen,Yoseph

Report Date : 23 Jun 1987

Pagination or Media Count : 10

Abstract : Method and system for detecting defects in the structure of a composite laminate material are described which comprise a first transducer for directing an ultrasonic beam of preselected frequency along a transmission axis onto a surface of the laminate at a preselected angle to generate Lamb waves in the laminate and leaky Lamb waves reflected therefrom; a second transducer for detecting the reflected leaky Lamb waves and for providing an output signal corresponding to the amplitude of the reflected waves; a fluid sonically coupling the laminate with the transducers; a positioning system for selectively positioning the transducers along the surface of the laminate to produce a set of output signals characterizing the laminate; and suitable electronics for receiving and processing the output signals and comparing them with signals characteristic of a defect free sample of the laminate.

Descriptors :   *PATENTS, *COMPOSITE MATERIALS, *LAMINATES, TRANSDUCERS, OUTPUT, SIGNALS, ULTRASONICS, ELECTRONICS, POSITION(LOCATION), REFLECTION, WAVES, SURFACES, TRANSMITTANCE

Subject Categories : Laminates and Composite Materials

Distribution Statement : APPROVED FOR PUBLIC RELEASE