Electromagnetic Acoustic Resonance Spectrometer
Original Publication Date: 1987-May-01
Included in the Prior Art Database: 2005-Feb-01
Described here is a new technique and apparatus for nondestructive evaluation (NDE) of a mechanical assembly containing one or more ferromagnetic elements. This technique is called "Electromagnetic Acoustic Resonance Spectrometry" (EMARS), because it relies on the use of an electromagnetic field that is scanned in frequency to seek out mechanical resonances in a mechanical assembly; the positions and the widths provide a "fingerprinting" information on the size and shape and structural and material properties of the assembly. The word "spectrometry" is used here (as is common in the field of optics) to indicate that the frequency of the sinusoidal variation of the field is scanned to obtain acoustic resonance line positions and shapes. An embodiment is indicated in the figure.