電磁超音波探触子により送信された超音波Lamb波S0モードのメタマテリアル内伝播特性

抄録

　Acoustic metamaterials with local resonance structures shorter than the elastic wave wavelength can have frequency bands where elastic wave propagation is suppressed due to their resonance characteristics. Ultrasonic guided waves, which are expected to be an efficient nondestructive evaluation method for long structures, have various modes. The authors have investigated the possibility of using an electromagnetic acoustic transducer (EMAT) to transmit these guided waves and selectively excite the modes due to the relationship between the coil pitch and wavelength. This paper focuses on the propagation behavior of S0 modes selectively transmitted by EMAT to acoustic metamaterials, and investigates the existence of frequency bands where wave propagation is suppressed and the degree of wave amplitude reduction.