Fig. 13From: Use of Higher-Harmonic and Intermodulation Generation of Ultrasonic Waves to Detecting Cracks due to Steel Corrosion in Reinforced Cement MortarEvolutions of the values of parameter R with time. The emitter transducer was supplied with two tones at the same time (f1 = 30 kHz, f0 = 2 kHz), and excited with 180 V. The vertical line (t = 1 day) indicates the onset of the accelerated corrosion test.Back to article page