Creep and Heat Resistance

Most bonds suffer continuous stress (loading) in use. Although the levels of stress may be low, the duration of exposure is likely to be long (weeks, months or, possibly, years).

The dynamic rupture of a bond demonstrating high bond strength and/or fibre tear gives no indication of the bonds durability to sustained loading. A simple analogy is a self adhesive label which can be peeled intact if pulled gradually, but tears when pulled quickly.

It is therefore necessary to subject bonds to creep resistance tests in order to assure long term durability.

The assessment can be extended to look at the resistance to elevated temperatures associated with some export markets. Low temperature performance of bonds is usually assessed by dynamic rupture in a chilled or freeze temperature chamber.

Smithers Pira Technical Investigations use a procedure developed as part of the work of multi client project with industry and government joint sponsorship. It has been used successfully in accounting for many problems of bond failure.