Adhesion ultrasonic testing

Installation for Ultrasonic Testing AKV-S is designed for testing of diesel motors pistons. Particularly, this device identifies the areas with cracks and lowered adhesion on interfacial boundary between niresist ring and base material. 

Smith, D.F. and C.V. Cagle, A quality-control system for adhesive bonding utilizing ultrasonic testing. Applied Polymer Symposia No. 3 (M J. Bodnar, ed.), pp. 411-434, 1966. 

Improvements in Ultrasonic Testing of Adhesive Bonds using the Wavelet Packet Transform (S. Tavroul and C. Jones, eds.), School of Engineering and Science, School of Mathematical Sciences, Swinburne University of Technology, Melbonme, Australia, 2006. 

Rose, J.L. and J.J. Ditri, Pulse-echo and through transmission Lamb wave techniques for adhesive bond inspection. British Journal of NOT, 34(12), 1992. GogUo, L. and M. Rossetto, Ultrasonic testing of adhesive bonds of thin metal sheets. NDT E International, 32 323-331,1999. 

Nondestructive testing (NDT) is far more economical, and every assembly can be tested if desired. However, there is no single nondestructive test or technique that will provide the user with a quantitative estimate of bond strength. There are several ultrasonic test methods that provide qualitative values. However, a trained eye can detect a surprising number of faulty joints by close inspection of the adhesive around the bonded area. Table 7.16 lists the characteristics of faulty joints that can be detected visually. The most difficult defects to be found by any method are those related to improper curing and surface treatments. Therefore, great care and control must be given to surface-preparation procedures and shop cleanliness. 

G. J. Curtis, Adhesively bonded structure nondestructive testing with acoustic methods, in Ultrasonic Testing, J. Szilard, Ed., John Wiley, 1980. 

D. F. Smith, and C. V. Cagle, A Quality Control System for Adhesive Bonding Utilizing Ultrasonic Testing, in Structural Adhesive Bonding, M. J. Bodnar, ed., Intersdence, New York, 1966. 

The most popular ultrasonic nondestructive testing application has been associated with thickness measurement of a test object and defect location within the particular test object. Most of the applications to date have been associated with the testing of homogeneous isotropic materials. Recent work has extended the basic ultrasonic test philosophy to the field of composite materials and adhesive bonding inspection. Unfortunately, many difficulties occur because of the inhomogeneous and anisotropic characteristic of a composite material. This section includes a review of the physical principles associated with ultrasonic testing and the particular items that must receive special attention when inspecting composite materials or adhesively bonded sections of a structure. 

G. J. Curtis, Nondestructive testing of adhesively bonded structures with acoustic methods. Ultrasonic Testing Non-Conventional Testing Techniques, pp. 495-554 (1982). 

Sonic Inspection. Sonic and ultrasonic methods are, at present, the most popular NDT techniques for use on adhesive joints. Simple tapping of a bonded joint with a coin or light hammer can indicate an unbonded area. Sharp, clear tones indicate that adhesive is present and adhering to the substrate in some degree duU, hollow tones indicate a void or unattached area. Ultrasonic testing basically measures the response of the bonded joint to loading by low-power ultrasonic energy. 

Cawley P, Hudson MJ (1988) The NDTof adhesive joints using ultrasonic spectrscopy. In Thompson DO, Chimenti DE (eds) Review of progress in QNDE 8B. Plenum Press, New York, pp 1377-1384 Curtis GJ (1982) Nondestructive testing of adhesively-bonded structures with acoustic methods, ultrasonic testing - non conventional testing techniques. Wiley, Chichester... 

There are also a number of more sophisticated non-destructive techniques (NDT) which measure the frequency response of the bonded component part and can thus identify the presence (or absence) of adhesive in the joint. These NDT methods use ultrasonic testing, whereby high-frequency, highly directional sound waves analyse the adherends and find hidden internal flaws [2]. 

Goglio L, Rossetto M. Ultrasonic testing of adhesive bonds of thin metal sheets. NDT E Int 1999 32 323-31. 

The membrane thickness reproducibility was tested over the wafer on 32 evenly distributed membranes. A mean thickness of 61.8 im (s.d. = 7.3 im) was found across the whole wafer, while a lower ( 4 im) typical standard deviation was found on more closely located membranes. Prior to measurements, the membranes are preconditioned in 0.1 M KC1. No degradation of the membrane adhesion was observed during an immersion of 2 hours in an ultrasonic bath containing 0.1 M KC1. 

A typical washcoat on a metallic structure is shown in Figure 25. The significantly stronger adhesion of the washcoat on the anodized metal can be illustrated by testing the adhesion of the coating layer by using an ultrasonic treatment. Whereas the untreated metal loses approximately... 

The test methods are subdivided into two categories, destructive and nondestructive methods. One of the latter, the ultrasonic method , is applied in special fields of adhesive technology, for example, in aircraft construction. It is based on the fact that sound waves in test pieces propagate differently, in dependence on the evenness of their structure, which can be disturbed by the presence of pores or imperfections, thus enabling the recording of failures. 

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