9 января, 2016 
Pokraskin Destructive testing usually involves uplifting samples from the production line and determining the performance of the adhesive bond by strength testing against a predetermined standard. This may not always be possible, especially if the adhesive has extended cure times but with fast-curing adhesives (cyanoacrylates or UV-curing products) the application of force to determine the failure load will verify the adhesive performance.
Non-destructive testing can be as simple as a visual inspection as a trained eye will detect a surprising number of faulty joints, including close inspection of the adhesive bond line at the joint periphery, misaligned parts or uneven adhesive bond lines.
Another method of non-destructive testing is to apply a proof load to the parts. Care must be taken to design the proof test so that it does not overstress the part and thus cause damage that will reduce its service life. A typical proof load might be 20% of the ultimate failure load.
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].
Perhaps a simpler method of determining the quantity — particularly for medium — to high-volume applications — is to weigh the quantity of adhesive dispensed from the application equipment or weigh component parts before and after adhesive has been dispensed.
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