| 摘要 |
FIELD: ultrasonic nondestructive testing of materials and articles. SUBSTANCE: proposed electromagnetic-acoustic converter is provided with at least three flat induction coils, three concentrators of magnetic fields coming in the form of truncated cones. Summary surface of lower bases of cones contacting magnets meets condition 0,1<Sl.b/Sm<0,7. Geometrical centers of concentrators are located on circumference which center matches center of converter and distances between adjacent concentrators satisfy condition amax = dl.c+(0-40mm). Each coil is fabricated in the form of two, as minimum, single-row spiral-shaped identical windings placed in symmetry relative to center of converter and bonded on dielectric plate with leads-out located inside windings, on both sides of coil. External turns of windings are positioned on circle circumscribed equidistantly from geometrical center of concentrator. Relation of area circumscribed around coil to area of upper base of concentrator satisfies condition 3<Sc.o/Su.c<40,, ceramic plate protecting coils against damage is installed immediately adjacent to coils, on side of object of test. EFFECT: simplified design and reduced dimensions of converter, raised durability, accuracy and reliability of tests. 6 dwg |
