Abstract
Experimental results from studies on the properties of ultrasonic propagation velocity and attenuation in hydrocarbon-based magnetic fluid are reported. The ultrasonic frequency used is 2 MHz and the measurement scheme is based on the pulse method. The external magnetic field intensity is varied from 0 to 550 mT and the angle between the magnetic field direction and the direction of ultrasonic wave propagation is adjusted from 0 to 90°. The ultrasonic propagation velocity and attenuation changes are dependent upon the intensity of the magnetic field and the elapsed time of application. Characteristic properties of ultrasonic propagation in magnetic fluid are observed. These particular results seem to be caused by clustering structures in the magnetic fluid. Based on these results, the inner structure of the magnetic fluid is analyzed experimentally and the application of non-contact inspection in opaque fluids by ultrasonic techniques is discussed.
