3D magnetovision scanner as a tool for investigation of magnetomechanical principles

摘要

The study was aimed at designing a system for measuring the distribution of magnetic field around different magnetic objects including Smart Magnetic Materials. A new type of 3D camera for monitoring the magnetic field intensity was constructed. The measurement principle is based on internal magnetics properties of materials and the reverse magnetostriction effect (also called the Villari effect). No external magnetizing field is assumed; the entire magnetic effect is due to magnetomechanical principles. A new generation of Honeywell magnetosensors were applied to measure field intensity in 3D. Small size of measurement area (1.5 mm~3) allows quasi-local measurement of magnetic field. In the measurement head also Hall probes were alternately used. The aim of this stage of research was to construct the set for measurement of strength of a very weak magnetic field (10 A/m) around the magnetic objects. In scanner construction three axes for displacement in directions consistent with sensor axis were applied, which permits measuring magnetic field vector in geometrical coordination. Specialized software for data acquisition, processing and visualization of magnetic field vector has been written. In preliminary parts of the work magnetic scanner system allows determination of correspondence between mechanical and magnetic quantities. Main applications for this type of system are: reverse magnetostriction and magnetostriction in smart magnetic materials and composites, martensitic transformation induces plastic strain in shape memory alloys, NDT investigation, identification of local plastic deformation and texture of ferromagnetic materials, magnetic polygraphy and others. Measuring system may be used both as an entirely autonomous system as well as an integrated one, also through joint control with a typical mechanical testing systems for static and fatigue tests.