Quantitative subsurface defect detection in composite materials using a non-contact ultrasonic system

Author

Cerniglia, Donatella ; Djordjevic, Boro B. ; Nigrelli, Vincenzo

Author_Institution

Dept. of Mech. & Aeronaut., Palermo Univ., Italy

Volume

1

fYear

2001

fDate

2001

Firstpage

751

Abstract

The results of an experimental study conducted to detect subsurface defects in a thick Gr/PPS composite test sample using a noncontact ultrasonic system are presented. Surface waves are generated by a pulsed laser and detected by an air-coupled capacitance transducer. By controlling the surface wave wavelength through a shadow mask, it is possible to control surface wave penetration depth in the sample. Surface wave peak-to-peak amplitude is related to the near-surface material condition. Results indicate that signal amplitude decreases as the width of the defect increases and an approximately linear relation can be deduced

Keywords

composite material interfaces; composite materials; surface acoustic waves; ultrasonic materials testing; air-coupled capacitance transducer; approximately linear relation; composite materials; noncontact ultrasonic system; pulsed laser; quantitative subsurface defect detection; shadow mask; signal amplitude; subsurface defects; surface wave peak-to-peak amplitude; surface wave penetration depth; surface wave wavelength; Acoustic transducers; Aerospace materials; Capacitance; Composite materials; Nondestructive testing; Optical pulse generation; Surface acoustic waves; Surface emitting lasers; Surface waves; Ultrasonic transducers;

fLanguage

English

Publisher

ieee

Conference_Titel

Ultrasonics Symposium, 2001 IEEE

Conference_Location

Atlanta, GA

Print_ISBN

0-7803-7177-1

Type

conf

DOI

10.1109/ULTSYM.2001.991833

Filename

991833