Abstract:Due to the indeterminacy of the influence of the curvature radius of the curved detection surface on the radiation sound field of angled SV wave EMAT, the deviations would occur in the defect detection capability and defect quantification/positioningaccuracy of the thickwalled pipe linefocusing angled SVwave EMAT. Thefinite element model for the radiation soundfield of linefocusingangledSV waveEMAT basedon plane/convex detectionsurfacesis established, the influences of the factorssuchasthe curvatureradius of the convex detection surface, number of turns of meanderline coil and design initial angle on the main lobe peak and width are studied. Subsequently, the detection results for the convex detection surface are compared with those for the plane detection surface. The results show that compared with the plane detection surface, the convex detection surface plays a role of focusing ultrasonic wave, which is specifically manifested by the increase of the main lobe peak on the focusing side by 2276% and the decrease of the main lobe width by 1056%. When the number of turns of the meanderline coil is increased to more than 28 turns, the increase of the number of turns of the coil has a limited effect on strengthening the main lobe peak. When the curvature radius is 1485×10-1 m, the design initial angle of the coil is 10 ° and the number of turns of the meanderline coil is increased from 10 to 28, the main lobe peak of the linefocusing SV wave increases by 10256%, and the main lobe width decreases by 5799%.