レーザー超音波法による肉厚測定に及ぼす表面凹凸の影響

（熱弾性効果とアブレーションの比較）

抄録

The wall thickness was measured using the laser ultrasonic method. The results from the finite element analysis show that the ultrasonic waves propagate parallel to the slope of the groove and therefore underestimate the thickness as they approach the apex. In the thermoelastic regime, the second reflection of longitudinal wave is not measured because the transverse wave is stronger than the longitudinal wave, and the first transverse wave is measured at that time. Therefore, if thickness measurements are made using the second reflection of longitudinal wave in ablation, an overestimation occurs, but if thickness measurements are made in the thermoelastic mode, no overestimation occurs.