Magnetic Nanofuids in Ultrasonic Testing

摘要

The use of the magnetic nanofuid as the bonding medium fnd an ever increasing application in ultrasonic non-destructive testing method.A thin layer of magnetic nanofuid which is adhered on the transducers face with a permanent magnet enhance the ability of movement and provide good bonding for transducers. Using the results of the hydrodynamical analysis and these ex- perimental data we evaluated the magnetic fuid losses when the transducer is moving along the tested sur- face. Measurements of the temperature dependence of the ultrasonic velocity, density, viscosity and surface tension of water-based, dodecane-based, kerosene-based, antifreeze-based magnetic nanofuids have been made. The obtained results can be use for the choice of an optimum type of magnetic nanofuid in the design of ultrasonic transducers.