PROBLEM TO BE SOLVED: To accurately measure the speed of a shear wave.SOLUTION: A shear wave propagating in a test object is measured by an ultrasonic wave at a plurality of measurement points. Based on the result of the measurement, frequency distribution on the shear wave is obtained and a wave component of a predetermined strength or more is selected for each frequency. The speed of the selected wave component is obtained.SELECTED DRAWING: Figure 1COPYRIGHT: (C)2018,JPO&INPIT【課題】せん断波の速度を精度よく計測する。【解決手段】検査対象を伝搬するせん断波を複数の計測点について超音波により計測する。その計測結果に基づいて、せん断波の周波数分布を求め、周波数ごとに、所定の強度以上の波成分を選択する。選択した波成分の速度を求める。【選択図】図１
