Which nondestructive testing method uses a search unit to transmit energy into a test surface?

Which nondestructive testing method uses a search unit to transmit energy into a test surface?

• A. Ultrasonic
• B. Radiographic
• C. Visual
• D. Magnetic Particle

Answer: (A)

Ultrasonic testing relies on a search unit, or transducer, to send high-frequency sound waves into the material and then receive echoes. The transducer converts electrical energy into mechanical waves and must be in contact with the surface through a coupling medium to transmit energy efficiently. As the waves travel and hit flaws or internal boundaries, echoes return to the transducer, allowing detection and sizing of defects or measurement of thickness. The other methods—radiographic uses radiation to view internal features, visual inspection relies on sight, and magnetic particle uses a magnetic field with iron particles—do not involve a probe that transmits energy into the test surface in the same way, so they don’t fit the description.

Ultrasonic testing relies on a search unit, or transducer, to send high-frequency sound waves into the material and then receive echoes. The transducer converts electrical energy into mechanical waves and must be in contact with the surface through a coupling medium to transmit energy efficiently. As the waves travel and hit flaws or internal boundaries, echoes return to the transducer, allowing detection and sizing of defects or measurement of thickness. The other methods—radiographic uses radiation to view internal features, visual inspection relies on sight, and magnetic particle uses a magnetic field with iron particles—do not involve a probe that transmits energy into the test surface in the same way, so they don’t fit the description.