| 摘要 |
PURPOSE: To detect a transversal reflection wave due to irregular reflection generated at a grain boundary and to automatically measure the depth, etc., of a hardened and cured layer by obliquely applying an ultrasonic pulse into the surface of a material to be measured with different acoustic impedance in depth direction and measuring the distance to a boundary by extracting a reflection wave from the boundary of the layer. CONSTITUTION: After desired measuring conditions are set by a panel operation part 40, a Z-axis motor M1, a θ motor M2, an X-axis motor M3, and a Y-axis motor M4 are driven, thus setting a probe 11 to a specific incidence angle. Then, a driver 47 is driven, a high-frequency drive signal with a specific width is fed to the probe 11 periodically, and the reflection wave is led to an amplifier 49 via a switching circuit 48. The amplifier 49 amplifies the inputted high-frequency signal, converts it from analog to digital 51, and stores the signal at a memory 53 in time series via an adder circuit 52. A setting circuit 54 generates a reset signal when an integration count exceeds a setting count, sends the data stored at the memory 53 to an operation part 46, and multiplies a passage time from the surface of a material to a boundary by sound speed to calculate the depth of a grain boundary. |
