Abstract: The present disclosure provides a wireless flexible magnetic sensor based on magnetothermal effect, and a preparation method and a detection method thereof. The magnetic sensor includes an aerogel substrate, and magnetic nanoparticles having magnetothermal effect that are attached to a surface of the aerogel substrate. The magnetic sensor is placed in the alternating magnetic field to be measured, and then a trigger signal is generated by a data collecting device and sent to an infrared camera. The infrared camera can collect temperature distribution information at different instants of time from the surface of the magnetic sensor. A curve of temperature rise changes at different positions on the surface of the magnetic sensor can be obtained by analyzing a temperature distribution image captured by the infrared camera. Thus, a spatial distribution of the strength of the alternating magnetic field at different positions on the surface of the sensor can be determined.

Abstract: The present disclosure provides a wireless flexible magnetic sensor based on magnetothermal effect, and a preparation method and a detection method thereof. The magnetic sensor includes an aerogel substrate, and magnetic nanoparticles having magnetothermal effect that are attached to a surface of the aerogel substrate. Themagnetic sensor is placed in the alternating magnetic field to be measured, and then a trigger signal is generated by a data collecting device and sent to an infrared camera. The infrared camera can collect temperature distribution information at different instants of time from the surface of the magnetic sensor. A curve of temperature rise changes at different positions on the surface of the magnetic sensor can be obtained by analyzing a temperature distribution image captured by the infrared camera. Thus, a spatial distribution of the strength of the alternating magnetic field at different positions on the surface of the sensor can be determined.

Abstract: A built-in S-typed array eddy current testing probe and a method for detecting defects of a tubular structure are provided. The probe includes an exciting coil part and a plurality of pick-up coil parts, wherein: the exciting coil part includes multiple bundles of exciting coil wires helically wound on a columnar coil former with a same interval; two bundles of exciting coil wires with an interval of 180° are connected at an end of the columnar coil former, actually being a same group of exciting coil wire bundles; each pick-up coil part consists of two rows of pancake coils; each four pancake coils which are closely arranged in a square shape form one differential eddy current testing pick-up unit; a final output signal is a result of additions between signals of opposite pancake coils and subtractions between signals of adjacent pancake coils in each differential eddy current testing pick-up unit.

Abstract: A built-in S-typed array eddy current testing probe and a method for detecting defects of a tubular structure are provided.