While research and development of Electro-Magnetic Acoustic Transducer (EMAT) technology has been active for several decades, hardened production inspection system applications remain limited. Applications remain limited despite the several and distinct advantages and EMAT probe can have over conventional piezoelectric ultrasonic devices. In addition to being comparable in ultrasonic wave mode generation and sensitivity, under proper design, an EMAT probe offers the following advantages for the production minded engineer: (1) no fluid couplant is required, (2) the test can be non-contact, (3) works on rough, dirty, and hot surfaces, (4) can be operated at very high scan rates, (5) easy to automate, and (6) capable of generating useful waves modes that are difficult to generate with piezoelectric devices. Basic elements of an EMAT system are explained and a comparison to conventional piezoelectric devices is made. By using real application cases, the benefits of EMATs are demonstrated. These real cases include: (1) flash butt-weld inspection, (2) mill roll inspection, (3) automotive laser weld inspection, and (4) tube & pipe inspection.
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