Accession Number : ADD006653

Title :   Method and Apparatus for Examining Structures Using Stimulated Acoustic Emission.

Descriptive Note : Patent Application,

Corporate Author : DEPARTMENT OF THE ARMY WASHINGTON DC

Personal Author(s) : Mason ,Warren P ; Beshers ,Daniel N ; Kuo,John T

Report Date : 24 Oct 1978

Pagination or Media Count : 8

Abstract : A vibrator is held in contact with a structure undergoing testing, such as an airplane wing. Vibrations are distributed through the structure and structural defects such as fissures will respond by emitting an acoustical signal. The acoustic signal may occur over a wide frequency range. A pick-up having a crystal transducer also makes contact with the surface of the structure to detect acoustic emissions. The crystal has a wide band response capable of detecting structural defect acoustic emissions. The pick-up has electrical leads connected thereto so that the acoustic emissions are converted to electrical signals which may be recorded or viewed on an oscilloscope. Movement of the pick-up across the surface of the structure will help determine the location of the structural defect. (Author)

Descriptors :   *Patent applications, *Defect analysis, *Acoustic emissions, Structural analysis, Acoustic signals, Vibrators(Mechanical), Stimulation(General), Airframes, Nondestructive testing

Subject Categories : Acoustic Detection and Detectors

Distribution Statement : APPROVED FOR PUBLIC RELEASE