Test of Elastic Constants and Ultrasonic Wave Mode Conversion of Isotropic Metals by EMAT

This paper presents a method to measure elastic constants of isotropic metals by Electromagnetic Acoustic Transducer (EMAT). The tested part is a standard CSK-Ⅱ A sample. The EMAT system generates longitudinal and transverse waves concurrently near the part surface. The measured longitudinal wave and transverse wave speeds are 5937.62 m ·s^-1 and 3241.20 m ·s^-1, respectively. The derived Young's Modulus and Poisson's ratio are 212.51 GPa and 0.288 1, respectively. The wave mode conversion efficiency is deducted to be 9.5%. The efficiency of longitudinal wave exciting is found to be 9.2% of that of transverse wave exciting. The presented method for elastic constant inspection shows high accuracy and great convenience with no couplant and with toleration to part's surface roughness, rust and corrosion.