Accession Number : AD0616100

Title :   GRAPHITE STRAIN TRANSDUCER.

Descriptive Note : Final rept.,

Corporate Author : TRANS-SONICS INC BURLINGTON MASS

Personal Author(s) : Cederlund,Thomas A.

Report Date : APR 1965

Pagination or Media Count : 44

Abstract : This study was conducted to determine the applicability of using a graphite monoparticulate layer transducer as a means of detecting sound vibrations in diaphragms. Interest for this study was provided by reported gauge factor values of several thousand in strain gauges using this graphite monolayer technique. Techniques were developed for the formation and deposition of monoparticulate graphite layers and their transfer to thin film substrates. Evaluation of deposited graphite layers as strain gauges showed gauge factors of 800 for strains of 500 microinches per inch. For strains of less than 50 microinches per inch, gauge factors decrease rapidly. Transduced audio signals, when detectable above the background noise of the sensor, are distorted and for the most part unintelligible. It is concluded that, because of sensor generated noise and the small changes in transducer resistance developed by low strains, the graphite monoparticulate sensor is not an optimum method to transduce audio vibrations in diaphragms. It appears, however, that the graphite monolayer transducer might have important application when sufficient strain is produced and where high gauge output is beneficial. (Author)

Descriptors :   (*ACOUSTIC DETECTORS, GRAPHITE), (*TRANSDUCERS, ACOUSTICS), (*STRAIN GAGES, GRAPHITE), MICROPHONES, DIAPHRAGMS(MECHANICS), SOUND, NOISE

Distribution Statement : APPROVED FOR PUBLIC RELEASE