INFLUENCE OF THE TEMPERATURE ON ULTRASONIC IMAGES GENERATED BY ARRAYS IN ASTM A36 STEEL

Abstract

The temperature often plays an important role in ultrasonic inspections, since the velocity of ultrasonic waves is highly influenced by it. To create ultrasonic images, not only the wave velocity is important but also the amplitude of the signals. The aim of this work is to verify the influence of the temperature on the signal-to-noise ratio (SNR) in ultrasonic images obtained from an ASTM A36 steel sample. The ultrasonic images were created applying the Total Focusing Method (TFM) in signals recorded using an ultrasonic array. The results showed the SNR increases linearly with the temperature for images obtained closer to the surface of the sample. For images obtained deeper in the sample, no variation in SNR related to the temperature could be noticed.