Non-destructive testing technology does not destroy parts or materials, can be directly tested on site, and is highly efficient. At present, there are five main types of non-destructive testing: Ultrasonic Testing, Radiographic Testing , Magnetic Particle Testing , Penetrant Testing, and Eddy Testing. Current Testing). Ultrasound is a mechanical wave with a frequency higher than 20 kHz. Frequencies commonly used in ultrasonic testing are 0.5-5 MHz. This kind of mechanical wave can propagate in the material at a certain speed and direction, and a heterogeneous interface (such as a defect or the bottom surface of the object to be tested) that has different acoustic impedance will produce reflection. This reflection phenomenon can be used for ultrasonic flaw detection. The most common one is pulse echo detection. When the pulse is detected, the voltage from the pulse oscillator is applied to the probe (detection element made of piezoelectric ceramic or quartz wafer). The e...
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