Method for examining a surface of a sample by means of ultrasoun

Details Method for examining a surface of a sample by means of ultrasoun Method for examining a surface of a sample by means of ultrasoun

1986-09-08

1988-03-15

Chapman, John

Measuring and testing

Vibration

By mechanical waves

G01N 2904

Patent

active

047304944

ABSTRACT:
A method for examining a layer having defects and in particular the thickness of a machining damaged layer on a surface of a sample by means of a focused ultrasound beam and a device for realizing the method are disclosed, in which a focused ultrasound beam is generated and ultrasound reflected by the sample is detected. Curves (called V(z) curves) representing the relation of the distance between a transducer detecting the reflected ultrasound and the sample versus the detection output are traced while varying the distance and this measurement is repeated while varying the frequency of the focused ultrasound beam. The propagation velocity of surface acoustic wave in the sample is calculated on the basis of the period in each of the plurality of V(z) curves and a frequency dependence characteristic curve for the propagation velocity is obtained. The thickness of the machining damaged layer in the surface portion of the sample is evaluated from inflection points in the frequency dependence characteristic curve.

REFERENCES:
patent: 4541281 (1985-09-01), Chubachi et al.
patent: 4603585 (1986-08-01), Atalar
Curtis, G. J., "The Use of Surface Elastic Waves in Examining Surface Mechanical Properties." In: Szilard, J., Ultrasonic Testing (New York, Wiley, 1982), pp. 302-303. TA 417.4.U4.
Atalar, A. et al., "Phase Imaging in Reflection with the Acoustic Microscope." Applied Physics Letters, vol. 31, No. 12 (Dec. 15, 1977), pp. 791-793.

Affiliated with

Also associated with

Rating

Method for examining a surface of a sample by means of ultrasoun does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method for examining a surface of a sample by means of ultrasoun, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for examining a surface of a sample by means of ultrasoun will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1920195