METHOD FOR DETERMINING STRUCTURAL CHARACTERISTICS OF PRODUCTS MADE OF POLYMER COMPOSITE MATERIALS AND DEVICE FOR ITS IMPLEMENTATION Russian patent published in 2023 - IPC G01N29/46 

FIELD: instrumentation.

SUBSTANCE: elastic vibrations are excited on the surface of the test product using a laser-ultrasonic transducer, and the reflected echo signals of these vibrations passing through the thickness of the product are received from the same surface by a broadband piezoelectric receiver. Excitation of elastic vibrations is carried out by a broadband signal in the spectral range of 0.1-20 MHz with pulses with an energy of 1-10 mJ, a duration of no more than 0.05 mcs and a repetition rate of at least 10 Hz. To determine the location of the discontinuity and its dimensions, an information signal is additionally recorded as a function of the change in the amplitude of the sound wave that has gone into the structure of the material of the tested product over time, and an information signal in the form of a vibrogram, on the basis of which, based on the change in the amplitude of the reflected echo signal, a scan is formed in the form of sequentially located points trajectories of movement of the laser-ultrasound transducer of graphic lines with distortions in amplitude each, corresponding to changes in the amplitude of the reflected echo signal to form a graphic field of the structure of the material of the controlled product along its thickness on the line of movement of this transducer.

EFFECT: ability to determine the geometric parameters of internal and external discontinuities in the structure of PCM.

2 cl, 25 dwg