Ultrasonics

When used as flaw detectors, ultrasonic devices locate defects in materials and bounce back images of the defects, thus revealing their shapes and locations. Nondestructive testing neither damages the object being tested, nor harms the person performing the test. Metals, glasses, ceramics, liquids, plastics, and rubbers can be evaluated by this technique. Nondestructive testing of forged parts A three-dimensional ultrasound scan of the face of a 30-week-old human fetus. © BSIP/Kretz Technik/Photo Researchers. Reproduced by permission. is now a standard manufacturing practice. The technique is used to detect corrosion in metal parts. It is also used to measure the thickness of many materials (with accuracy of up to 0.0001 in [0.00025 cm] for metals, and 0.001 in [0.0025 cm] for plastics), including concrete structures. Farmers have even used ultrasound to measure the fat layers on their cattle prior to sending them to market.