Nondestructive testing of 2017 aluminum copper alloy diffusion welded joints by an automatic ultrasonic system
The quality assurance of diffusion welded joints of 2017 aluminum copper alloys has been performed by ultrasonic nondestructive testing (NDT) at high frequency ranges. An ultrasonic automatic system with a high frequency pulser receiver focused probe (D = 15 MHz) was used to detect and artificial calibrated discontinuity (tungsten wire) with an opening diameter of 25 {micro}m (1 x 10{sup {minus}3} in.), in a scanned area of 0.25 mm{sup 2} (4 x 10{sup 4}in.{sup 2}). By this technique, it was also possible to detect clusters of residual microdiscontinuities and some unwelded zones predicting the state of the welded joints, before their dynamic tensile loading test. The difference between a sound and a rejectable welded joint was made by comparison with an ultrasonic autograph image of a treated sample which was the base material specimen subjected to the same thermal cycle as the welded sample. Furthermore, the reflected echoes of the welded samples, as well as the dynamic stress elongation behavior of loaded samples, were compared to those of a treated base material. The average magnitude of the reflected echoes of the extracted curves, arising from a sound welded joint corresponded to a total average value of 45.6 dB, whereas those of a bad joint were equal to 80.2 dB. Thus, beyond this last value it is concluded that the dynamic mechanical properties of diffusion welded joints become often very weak.
- Research Organization:
- Societe Les Roches, Nantes (FR)
- OSTI ID:
- 20005645
- Journal Information:
- Materials Evaluation, Journal Name: Materials Evaluation Journal Issue: 12 Vol. 57; ISSN MAEVAD; ISSN 0025-5327
- Country of Publication:
- United States
- Language:
- English
Similar Records
Symposium on Nondestructive Evaluation, 14th, San Antonio, TX, April 19-21, 1983, Proceedings
Evaluation of ultrasonic techniques for detection of stress-corrosion cracks in stainless steel piping. [100 and 250 mm]