ACOUSTO-ULTRASONIC (AU) TECHNOLOGY
Through a Small Business Innovative Research Project sponsored by the U.S. Army Tank Armament and Automotive Command (TACOM
), we have developed the Acousto-Ultrasonic (AU
) technology as an inspection technique for use in government and industry.
technology consists of sending low frequency acoustic pulses at a predetermined angle of incidence into a material under inspection. These acoustic pulses travel through the material and are reflected by the different interfaces inside the sample. If a discontinuity (delamination, debond etc.) is present inside the material, the reflected acoustic energy changes, revealing the presence of the discontinuity.
Originally intended for the inspection of multifunctional composite armor, we have been using the AU
technology extensively in the inspection of other critical composite structures such as:
Graphite/epoxy, foam-core composite centrifugal arms for simulators
Offshore platforms Fiber Reinforced Polymers fire system piping
LAU 7 composite nitrogen receivers
Type III Navy diving bottles
Small Arms Protective Inserts (SAPI) for personal armor.
In order to determine the optimal inspection parameters for a particular composite structure (incidence angle, frequency, and pulse length), a wave propagation model for multi-layered structures is used. This model is based on a plane wave propagation model using the Thomson-Haskell transfer matrix for multilayered media. The characteristics of the composite material such as layout and material properties, are used as input data to the model.