Fundamentals of Electromagnetic-Acoustic-Transformation Thickness Measurements with Attachable Probes: IV. Inverse and Double Electromagnetic-Acoustic Transformation in a Tangential Polarizing Field

摘要

Calculations are performed for projections of the induction of the secondary field in air, which arises after inverse and double electromagnetic-acoustic transformations in a solid ferromagnetic conducting body via the induction and magnetic transformation mechanisms, for arbitrary values of this body's macroscopic parameters and the radiation frequency lying in a quasi-stationary range. The distributions of the emf induced in the measuring coil by the normal projection of the secondary field upon the first and second sound reflections are presented. It is shown that these distributions are identical to the distributions observed in a normal polarizing field, and this identity is explained. Additional experimental and theoretical data are presented in favor of the use of the magnetostriction transformation mechanism during the construction of a thickness gage with spatially separated emitting and measuring coils that is placed on ferromagnetic articles.