105 results about "Ferrocobalt" patented technology

The invention provides a torsional mode guided-wave magnetostrictive sensor based on a double-ring permanent magnet array. The sensor mainly comprises two symmetrical semi-ring sensor components which are connected and coated on the pipeline surface through an elastic fastener. Each semi-ring sensor component mainly comprises a double-row permanent magnet array, two ferrocobalt strips, detection coils, a rubber shell and an epoxy resin layer; the two ferrocobalt strips are pre-bent into an arc to adapt to an outer diameter of a tested pipeline, and two sides are fixed by a molding base; the detection coil is wound on the two ferrocobalt strips in a fixed spacing manner, and alternating current is introduced to form an alternating magnetic field along the length direction of the ferrocobalt strips; rectangular permanent magnets in the double-row permanent magnet array are adsorbed on the outer sides of the ferrocobalt strips in the same direction, and a static magnetic field along the width direction of the ferrocobalt strips is provided. Alternating current signals with a phase difference of 90 degrees are introduced into two groups of detection coils in the sensors, and direction controllable torsional mode guided-waves are generated to be used for pipeline defect detection.