Nizamitdin  Muhtarov, Lenar R.  Sarimov, 
    The Digital Ultrasonic Interferometer For Quality Inspection of Piezoelectric Crystals,
    Journal of Engineering and Applied Sciences,
    Volume 11,Issue 4,
    2016,
    Pages 695-697,
    ISSN 1816-949x,
    jeasci.2016.695.697,
    (https://makhillpublications.co/view-article.php?doi=jeasci.2016.695.697)
    Abstract: Researcher refers to hypersonic measurement technique. A digital hypersonic method for quality inspection of piezoelectric crystals. The method is grounded on automatic metering of a time interval between echo pulses and Supersonic Wave Attenuation (SWA) in an inspected article with information output in a digital form. The hardware and functional features of hypersonic system is presented. The method can be used in factory and scientific laboratories to obtain express-information on quality of ingoing materials for fabricated items.
    Keywords: Velocity;absorption;amplitude;frequency;;Q-factor;duration